OFFICIAL JOURNAL OF THE AUSTRALIAN SOCIETY FOR MICROBIOLOGY INC. Volume 29 Number 4 November 2008 2009 Annual Scientific Meeting ASM’s Golden Jubilee Year! Perth Convention Centre 6-10 July 2009 Infections in Pregnancy and the Newborn OFFICIAL JOURNAL OF THE AUSTRALIAN SOCIETY FOR MICROBIOLOGY INC. Vertical Transmission 170 First Words 172 From the Editors 173 In Focus and Under the Microscope articles 174 Page 179 Serology testing for syphilis in pregnancy: is it still relevant? 174 Congenital and perinatal cytomegalovirus (CMV): has diagnosis improved in 30 years? 176 What happens when a baby dies: stillbirth investigations for infection and other aetiologies 179 When a baby dies: stillbirth from the community perspective and what parents want to know 184 Longer-term outcomes of infections in pregnancy: pathogenesis of diabetes and other chronic infections 186 Toxoplasmosis in pregnancy: often suspected, rarely convicted 188 Page 188 Diagnosis and treatment of herpes simplex virus (HSV) infection in the newborn 194 Respiratory infections in the newborn 197 Pathogenesis of cytomegalovirus (CMV) infection in pregnancy 200 Pathogenesis of malaria in pregnancy 204 Goal setting and reality: maternal, perinatal and childhood malaria 208 Infection and preterm birth 212 Mother-to-child transmission of HIV: positive impacts 215 Intrauterine infection: preterm birth and pulmonary impact Page 212 217 ASM Affairs 220 What’s On 223 Who’s Who 224 M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 November 2008 Volume 29 Number 4 169 Vertical Transmission The Australian Society for Microbiology Inc. Unit 23, 20 Commercial Road Melbourne VIC 3004 Tel (03) 9867 8699 Fax (03) 9867 8722 Email [email protected] www.theasm.com.au ABN 24 065 463 274 For Microbiology Australia correspondence, see address below. Editorial team Prof Ian Macreadie, Mrs Jo Macreadie Editorial Board Dr Ailsa Hocking (Chair) Prof Mary Barton Prof Linda Blackall Dr Chris Burke Prof Peter Coloe Assoc Prof David Ellis Dr Ruth Foxwell Dr Geoff Hogg Dr Ipek Kurtböke Dr Gary Lum Prof William Rawlinson Assoc Prof Lindsay Sly Dr Paul Selleck Dr David Smith Ms Helen Smith Prof Hatch Stokes Dr Paul Young Subscription rates Current subscription rates are available from the ASM Melbourne office. EDITORIAL correspondence Prof Ian Macreadie/Mrs Jo Macreadie CSIRO Molecular & Health Technologies 343 Royal Parade, Parkville VIC 3052 Tel (03) 9662 7299 Fax (03) 9662 7266 Email [email protected] Published four times a year by a division of Cambridge Media 128 Northwood Street West Leederville WA 6007 www.cambridgemedia.com.au Copy Editor Ceridwen Clocherty Graphic Designer Gordon McDade Advertising enquiries to Simon Henriques, Cambridge Publishing Tel (08) 9382 3911 Fax (08) 9382 3187 Email [email protected] © 2008 The Australian Society for Microbiology Inc. All rights reserved. No part of this publication may be reproduced or copied in any form or by any means without the written permission of the Australian Society for Microbiology. Unsolicited material is welcomed by the Editor but no responsibility is taken for the return of copy or photographs unless special arrangements are made. ISSN 1324-4272 The opinions expressed in articles, letters and advertisements in Microbiology Australia are not necessarily those of the Australian Society for Microbiology or the Editorial Board. 170 Hatch Stokes President ASM Planning for the national meeting in Perth is now very much in full swing. As mentioned previously, we hope to make this meeting extra special as the Society will be turning 50 in 2009. We will have the usual impressive array of international speakers that will include Bonnie Bassler as the Rubbo Orator. In addition, the American Society for Microbiology has very generously agreed to sponsor an additional speaker to this meeting to help us celebrate our 50th anniversary. Following an approach from the Perth LOC, I am pleased to be able to announce that Rita Colwell has accepted an invitation to attend the conference and speak. As many of you know, Rita has a number of links to Australia and has attended past meetings. Another important positive outcome for us in 2009 is that Australia Post has agreed to produce a commemorative edition pre-paid envelope, the release of which we hope to time with the National conference. These envelopes prove very popular and ours will be available through post offices nationwide. The Editorial Board of Microbiology Australia will be working with Australia Post on a suitable distinctive design so this is definitely something to look out for. The ASM has also commissioned a history consulting company to write a short history of the Society to be completed by the Perth meeting. This will be a ‘living history’, drawing on information from prominent members who helped shape the earlier years of the Society. The interviews of these people have now been completed and we will have the final draft document in a couple of months. At that time we will decide in what form this history will be made available to members and the general public. Now is a good time to remind everyone that planning is also underway for the National meeting to held in Sydney in 2010. If you have suggestions for the scientific programme, either for international speakers or symposium themes, I would encourage you to contact the relevant members of the National Scientific Advisory Committee. These are Andy Holmes (the Scientific LOC Chair for Sydney) or Jon Iredell, Peter White, Linda Blackall and Ruiting Lan (the Division 1, 2, 3 and 4 Chairs respectively for Sydney). On a related theme, we are also keen to get suggestions from members for the Visiting Speakers’ Program. Suggestions can be forthcoming at any time so, for example, if you have an international visitor to your lab, let Carol Ginns at the National Office know and we may be able to support them visiting other parts of the country to speak. I was recently in Istanbul representing the Society at the International Union of Microbiological Societies (IUMS) Congress. This congress is held every 3 years and, as well as myself, TuckWeng Kok and David Ellis also attended on your behalf. Our attendance is supported to a large extent by the Australian Academy of Science to whom we are grateful. This is a useful exercise as it is an opportunity to network and discuss matters important to us all. The feedback from our British and American colleagues in regards the new postgraduate travel awards established between us and their respective societies was overwhelmingly positive. I am therefore optimistic that these will become long-term initiatives. One other positive outcome of the Congress for us was that TuckWeng was elected to the Scientific Advisory Board of the International Congress of Virology for a 3 year term; congratulations TuckWeng. Finally, I draw your attention to the fact that we have recently revamped the rules for the awarding of Distinguished Service Awards. The details can be found on the ASM website. The closing date for nominations is 30 November. Please consider nominating someone you would consider appropriate for one of these important awards. MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 MRSA SeRiouS infection SeRiouS ReSultS 1 MRSA = Methicillin-resistant Staphylococcus aureus. PBS Information: this is not listed on the PBS. Please review Product Information before prescribing. Full Product Information is available on request from Pfizer. ZYVOX® (linezolid). Indications: Infections due to resistant organisms, including MRSA and VRE. No clinical activity against Gram-negative pathogens. Contraindications: Hypersensitivity. Precautions: Monitor blood in certain populations. Antibiotic-associated pseudomembranous colitis. Reports of serotonin syndrome when co-administered with serotonergic agents. Symptoms of visual impairment; monitor visual function. Convulsions (rare). Safety and effectiveness following 28 days not established. Gram-negative pathogens. Pregnancy: Category B3. Lactation: discontinue. Adverse Effects: Headache; candidiasis; taste perversion; GI disturbances; peripheral and optic neuropathy; lactic acidosis; angioedema; rash; myelosuppression; bullous skin disorders; serotonin syndrome (very rare); abnormal haematology and liver function tests. Interactions: Tyramine; serotonergic agents; vasopressive/ dopaminergic agents. Dosage and Administration: IV (30−120 min infusion) or oral bid (with or without food). Adults: CAP/nosocomial pneumonia: 600 mg IV or orally for 10 to 14 days; SSTI: 400 mg to 600 mg orally or 600 mg IV for 10 to 14 days; enterococcal infections: 600 mg IV or orally for 14 to 28 consecutive days. Children and adolescents: nosocomial pneumonia and SSTI: 10 mg/kg IV or orally qid for 10 to 14 days; enterococcal infections: 10 mg/kg IV or orally qid for 14 to 28 days. Neonates: refer to full PI. Based on Full Product Information, TGA approved 15 November 2005. Date of most recent amendment: 4 April 2008. Minimum Product Information prepared 29 January 2007. 1. ZYVOX Approved Product Information. Pfizer Australia Pty Limited, ABN 50 008 422 348, 38-42 Wharf Road, West Ryde NSW 2114. Medical Information: 1800 675 229. www.pfizer.com.au H&T PZR0054/MA. First Words Infections in pregnancy and the newborn William Rawlinson Senior Medical Virologist SEH & UNSW Head, Virology Division, SEALS Microbiology Prince of Wales Hospital Randwick NSW 2031 Tel (02) 9382 9113 Fax (02) 9398 4275 Email [email protected] ... about in 1951 I met in Oxford a very well known scientist and I said to him that I was a friend of Eccles. And he said Eccles [recipient of the Nobel prize for physiology 1963], [was a] very good man but you know the man must be a bit crazy. He refutes his own theories. Sir Karl Popper There are many important issues relating to the investigation of infections during pregnancy and immediately after birth. They relate to the scientific areas of the need for diagnosis, for definition of markers of infection, and for the use of surrogate markers of severity, as well as clinical areas relating to diagnostic and therapeutic interventions. Ideally, at the same time, the integrity of any scientific research done to understand the pathogenesis of damage to the fetus and neonate must not be compromised. Further, the important area of parental involvement in decision making, often at a time of intense emotion, must be carefully integrated into this process. With parental consent, studies of infections of pregnancy, neonates, and adverse outcomes of pregnancy can be made more effective with a multi-disciplinary approach. Many of the authors of the articles in this issue of Microbiology Australia have been involved in such approaches to research, diagnosis and therapy of congenital and perinatal infections. In this edition we have papers discussing pathogenetic studies of the role of prenatal infections in later clinical outcomes such as the role of infection in precipitating spontaneous preterm birth, the possible role of enteroviral infection in type 1 diabetes mellitus, and the pathogenesis of damage from cytomegalovirus in pregnancy. In the clinical setting, there are important papers summarising our understanding of infections with malaria, cytomegalovirus, toxoplasmosis and HIV during pregnancy, as well as herpes simplex and respiratory viruses in the newborn. We also have an article specifically on the personal and social consequences of stillbirth – a problem which results in almost as many deaths in Australia each year as from breast cancer. with various adverse outcomes of pregnancy, we must avoid simplistically linking association with causation. Infections need to be seen in the context of the maternal-placentalfetal interaction that develops during pregnancy, the changes in the immune system as the fetus is born, and neonatal immunological development. We should consider the results of diagnostic testing as a whole, including all possible information from serological, molecular, microbiological and histopathologic sources. These need to be related to the clinical setting, as testing may be adjunctive, rather than definitive, in the diagnosis of fetal or neonatal damage. We need to be aware of the utility, as well as the limitations, of our current knowledge. What is important about many of these studies is that the list of potential aetiologies of many conditions is being expanded by the use of nucleic acid and other molecular techniques to define the organisms present more clearly. It is useful to examine these studies using criteria suggested by Karl Popper – we utilise observation, but such observation is selective and driven by theory. Indeed, as he stated succinctly “Our knowledge can only be finite, while our ignorance must necessarily be infinite.” It is our ability to use the scientific observations relating infection to adverse outcomes of pregnancy and infection in the neonate to inform our current practice that is important for the patients who seek our assistance currently. It is equally important to be able to discard these scientific findings if new findings prove our hypothesis incorrect. The importance of continuing research in this area cannot be underestimated. Establishing what organisms are important in different adverse pregnancy outcomes, the nature of placental, fetal and neonatal infection with these organisms and the associated host response is vital. The determination of causality (or not) needs to follow soon, if we are to introduce therapeutic and preventive strategies. Fortunately, there are microbiologists, clinicians and members of the community who are interested in the scientific, clinical, social and personal consequences of infections in pregnancy and early infancy. These are people who continue to propose theories, study and research in this area. They remain prepared, like Sir John Eccles, to use the scientific method to discard incorrect theories, and propose new testable hypotheses. Some of them are represented in the papers presented in this edition of Microbiology Australia, and I hope you find their insights useful. Professor William D Rawlinson (MBBS, PhD, FRACP, FRCPA) is the head of the Virology Division at SEALS, Conjoint Professor at UNSW and infectious diseases physician at Prince of Wales Hospital, Sydney Children’s Hospital and Royal Hospital for Women. His research position involves supervision of several groups who undertake basic research into the pathogenesis of viral illnesses, with integration of these basic studies into clinical outcomes. In reviewing the findings from studies associating infections 172 MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 From the Editors Microbiology Australia: have your say How is Microbiology Australia meeting your interests? We would love to know. We have worked with the Editorial Board for 3 years now trying to present you with issues that are of relevance, even though they may sometimes fall outside your area of immediate interest. In this way, ASM’s microbiologists can be kept up to date with the breadth of microbiological developments. Some of these issues are relevant beyond our society and so the issues are now also made available to journalists and science writers. In some cases, journalists have worked with our contributors and built major feature articles. We are often asked how themes for issues are decided upon. The Editorial Board makes these decisions about a year in advance in response to what we think the ASM membership wants to hear. Your input is highly valued! Another key factor is whether there will be Guest Editors and sufficient contributors to provide material for an issue. Guest Editors are key people in their field and have strong connections or knowledge with their field. They are able to pull together a cross section of contributions that provide a comprehensive overview of an area. This can be a very daunting task and sometimes there are difficulties about what can be said on more contentious issues. Issues coming up soon include water, climate change and indigenous health. We would like to take this opportunity to thank everyone who contributes to MA. The list includes the Editorial Board, Guest Editors, contributing authors, reviewers, the National Office, advertisers, and our publishers Cambridge Media who always do a great job in working with us to meet all our requests. In the last issue, an excellent issue on Staphylococcus aureus, we were able to move deadlines forward and complete the print run of 3400 to get copies to Cairns so all registrants at the 13th International Symposium on Staphylococci and Staphylococcal Infections meeting received a copy. In the issue before, on biosecurity and biosafety for microbiology, new rules for microbiology were enunciated. These have a significant impact on many in the ASM. We took a special personal interest in the current issue because we were blessed with two new grandchildren in the past few months and one contracted respiratory syncytial virus (RSV) at just 4 weeks of age. This required hospitalisation to control the symptoms and was obviously of concern. We are certainly glad of the modern techniques to enable the diagnosis and to provide care but obviously there are needs for research into therapeutics to prevent or control diseases such as RSV and other children’s diseases. Finally, as this is our last issue for the year, we want to wish you well for the forthcoming holiday season and New Year. Ian and Johann Macreadie M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 In Focus Serology testing for syphilis in pregnancy: is it still relevant? Peter W Robertson SEALS Area Serology Laboratory Prince of Wales Hospital Barker Street, Randwick NSW 2031 Tel (02) 9382 9153 Fax (02) 9382 9151 Email Peter.Robertson@sesiahs. health.nsw.gov.au Until the emergence of HIV and other more spectacular viral diseases, syphilis has probably been referred to more than any other infectious disease throughout history – in theatre, literature and politics. During the 19th century, aside from being a notorious disease transmitted sexually, it was the diverse clinical and pathological forms of syphilis which led to much of this mystique and fear. The main consequences of syphilis are the long-term effects of dementia or damage to the cardiovascular and central nervous systems or transmission to the fetus during pregnancy . Prior to 1 the introduction of the Wassermann complement fixation test in 1906, there was no laboratory confirmation for the diagnosis of syphilis and the manifestations of many other diseases – for example most inflammatory diseases of the eye, a number of psychiatric conditions and congenital malformations – were incorrectly attributed to syphilis. After the 1940s, a variety of penicillin-based clinical treatments in pregnancy were shown to effectively prevent neonatal transmission of syphilis. Consequently, this disease began to decline. The success of penicillin also reflected a decline in the number of cases of syphilis in the general community. Antenatal testing One of the most tragic consequences of syphilis is congenital syphilis. Congenital syphilis is the result of transplacental passage of Treponema pallidum from an infected mother. This occurs when a mother is infected or becomes infected during pregnancy. As with other intrauterine infections, there is a widespread spectrum of disease ranging from intrauterine death to mild effects. Because of this wide spectrum, it has been estimated that many infections go unnoticed 2. However, some specific pathological and radiological signs are unique to this infection. 174 Serological screening for syphilis during pregnancy is advocated because the effective prevention of congenital syphilis depends on the diagnosis and treatment of the disease in a pregnant woman. Unlike other causes of intrauterine infection such as rubella and cytomegalovirus, syphilis does not have to be acquired during the pregnancy. Serology should be carried out as part of antenatal screening, preferably at the first prenatal visit. Maternal treatment in preventing congenital syphilis has an overall success rate of >98% 3. Most failures of maternal treatment in preventing congenital syphilis occur if the mother is in the secondary stage, the most infectious stage of the disease. Success rates of maternal treatment also vary with the gestational age at which treatment is initiated. Most successful outcomes occur when the disease is diagnosed and treated early in the course of the disease, as the success rate in preventing congenital infection may be as low as 90% after 26 weeks 3. This emphasises the need to test at the first antenatal visit. Apart from management of the pregnant woman with syphilis, information regarding the disease status of partners must also be obtained. Contact tracing and testing of the partners of women diagnosed with syphilis in pregnancy is important in order to prevent re-infection during the pregnancy. The CDC recommends that these women should also be tested for HIV 4. Recently, the testing strategies for syphilis screening in pregnancy have changed largely due to the development of automated enzyme immunoassays using recombinant antigens of T. pallidum. Prenatal screening using Reagin serological tests is still feasible and affordable in most undeveloped countries. One issue, however, is that some of these non-treponemal Reagin tests are prone to giving false-positive results in pregnancy. Consequently, all positive results must be confirmed with treponemal-specific tests. Conversely, if treponemal-specific tests are used for screening, a Reagin test (usually RPR) is required to determine the stage of the disease and as a base line for monitoring treatment. Once the mother has been treated during pregnancy, sequential titres using RPR or other Reagin assays should be performed to monitor the response to treatment. Although not common in Australia, serological testing and interpretation of results is complicated in women who have been infected with HIV. This may be further complicated in intravenous drug-users whose serum can give false-positive Reagin tests. Testing of the newborn Congenital syphilis is largely a preventable disease. However, it continues to be an important public health problem both in developed and developing countries. Even with treatment during pregnancy, CDC recommendations are that all infants born to women who have positive serological tests during pregnancy should be examined thoroughly for evidence of infection, including microscopic examination of placenta or umbilical cord using a specific fluorescent staining 4. MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 In Focus Serological evidence of congenital infection in the past could only be established by following the decline of maternal antibody or persistence of antibody in the neonate during the first 6 months of life. This has a number of disadvantages, in that the actual decline in the Reagin will depend on the gestational age of the baby and the titre of Reagin in the mother’s serum at delivery. The development of specific IgM assays, including the IgM FTA, has made the serological diagnosis of syphilis more convenient and practical. Overall, decisions on treatment will result after examination of clinical, laboratory and radiographic evidence of congenital syphilis. Table 1. Infectious syphilis in south-eastern Sydney 2001-2007 6. Year Patients with infectious syphilis: 2001 0.46% (61.4% male) 2002 0.68 (73.6% male) 2003 1.44 (73.2% male) 2004 1.60 (81.7% male) The argument for continued screening 2005 1.39 (83.7% male) During the 1990s, some experts were suggesting that syphilis would soon be eradicated from Western society. In the USA, syphilis testing was mandatory before marriage licences could be obtained in several States, but over the years this requirement lost support and, as of 2008, Mississippi was the only State in USA still requiring couples to take a blood test for syphilis before marriage. Following these decades of decline, in 2000 overall rates of syphilis began rising throughout the developed world, especially in sexually active homosexual men. An increase in the rates of infectious syphilis in south-eastern Sydney between 2000-2004 was reported 5 and continues to the present time (Table 1) 6. 2006 1.95 (84.8% male) 2007 1.95 (86.1% male) Various factors have been blamed on the resurgence of syphilis in this century, including ‘safe sex fatigue’ and the evidence that decline in safe sex behaviour has occurred since antiretrovirals were introduced in 1990s. In some cases, journalists have blamed the internet for the increase in the sexually transmitted disease due to the rise in the number of net-based networks of infected men seeking partners for unprotected sex. The Australian national notifications of congenital syphilis rose in 2001 (Table 2) 7, possibly reflecting a spill into heterosexuals and bisexual males. This figure does not, however, reflect the number of infections diagnosed and treated in pregnancy. In Australia, syphilis screening during pregnancy is reimbursed by Medicare in a series of items. In 2006/07 the cost of reimbursement of these antenatal screening items was more than $9.6m. Antenatal syphilis screening is not itemised separately but is grouped with various combinations of other screening tests, including hepatitis C, hepatitis B and rubella. Thus it is not possible to determine how many syphilis tests were carried out during pregnancy in Australia to estimate a cost benefit analysis. The resurgence of syphilis infections and the knowledge that congenital syphilis, a devastating disease, can be prevented by antenatal treatment leaves no doubt that testing for syphilis in pregnancy is still relevant. One risk is that, in many people’s minds, the disease does not tend to be associated with patients in higher socioeconomic groups and, to avoid offending these patients, syphilis testing is not included in the request for an antenatal serological screen. There are a number of well documented instances where this has had disastrous consequences. This mindset is also reflected in the changes that were made to the Medicare item for antenatal serological screening – previously M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 as a % of population and broken down into gender Table 2. Notifications of congenital syphilis 7. Year and no. notifications 1998 4 2003 13 1999 4 2004 13 2000 5 2005 15 2001 21 2006 13 2002 18 2007 8 it was mandatory to include syphilis testing, but the item was changed so that now syphilis screening in pregnancy has become optional. References 1. 2. 3. 4. 5. 6. 7. Silverstein, A.M. and Ruggere, C. (2006) Dr Arthur Conan-Doyle and the case of congenital syphilis. Perspect. Biol. Med. 49, 209-219. McFarland, B.L. et al. (1994) Epidemic syphilis – maternal factors associated with congenital infections. Am. J. Obstetrics Gynaecol. 170, 535-540. Alexander, J.M. et al. (1999) Efficacy of treatment for syphilis in pregnancy. Obstetrics Gynaecol. 93, 5-10. Center for Disease Control and Prevention (2006). Sexually Transmitted Diseases Guidelines. US Department of Health and Human Services. Botham, S.J. et al. (2006) Epidemic infectious syphilis in inner-city Sydney: strengthening enhanced surveillance. Aust. NZ. J. Public Health 6, 529-533. Robertson, P. et al. (2007) An epidemic increase in infectious syphilis (IS in south-eastern Sydney 2001-2007). National Serology Reference Laboratory Workshop 2007. National Notifiable Diseases Surveilance System. Australian Govt. Dept of Health and Ageing ( 2008). Peter Robertson supervises the SESIAHS Area Serology Laboratory, which is also a State reference laboratory for HIV diagnosis, as well as having an active role in teaching and research. Recently, his main research interest has been in the development and evaluation of an antibody assay for diagnosis of invasive Meningococcal disease (IMD) and for evaluating responses to N. meningitidis serogroup C vaccine. He has twice been invited to deliver lectures on serological diagnosis at the National Institute of Health in Maryland USA and has been author of more than 50 publications in refereed journals. One of his most important achievements was using IgA antibody to identify Bordetella pertussis as a major cause of chronic cough in adults, a study he published in 1987. This study prompted developed countries to alter vaccination strategies in an attempt to eliminate this debilitating disease in adults. 175 In Focus Congenital and perinatal cytomegalovirus (CMV): has diagnosis improved in 30 years? Jonathan Howard, Beverley Hall and William Rawlinson Virology Division, Dept of Microbiology, South Eastern Area Laboratory Services Prince of Wales Hospital, Randwick NSW 2031 School of Medical Sciences and Biotechnology and Biomolecular Sciences, University of New South Wales Sydney NSW 2052 Tel (02) 9382 9113 Fax (02) 9398 4275 The implication of a diagnosis of cytomegalovirus (CMV) during pregnancy or in the neonatal period remains uncertain despite our increased understanding of the pathophysiology of the disease. Current tests for CMV include serological tests (usually EIA IgG, IgM, avidity) and nucleic acid testing (NAT). When used together, these tests offer improved reliability in diagnosis of CMV in pregnant women and infants. Diagnosis in pregnant women Congenital CMV infections may be the result of either a primary or recurrent infection. Less than 5% of pregnant women with primary CMV infection are reported to be symptomatic 1 and most CMV infections are asymptomatic during the acute stage 2. There are many diagnostic procedures for the detection of CMV 3, 4; however, there is no adequate single test. The primary concern to most pregnant women and their medical advisors is a diagnostic test that predictively defines the clinical outcome for the baby. Virological and serological testing of the mother is necessary to establish a diagnosis. Documented seroconversion of the mother from IgG seronegative to IgG seropositive is the definitive method of determining a primary CMV infection. CMV IgM positivity is used extensively as a marker of active or recent infection, but IgM positivity does not always correlate with primary infection. Indeed, older studies suggest IgM antibody may not be detected until 6-9 months after the acute phase of a primary infection in a small number of women 5. IgM detected using modern sensitive enzyme immunoassay (EIA) methods may persist for years postprimary infection in a proportion (5-10%) of infected women 6, 7. During reactivations or reinfections, pregnant women may also test IgM positive and excrete CMV in their urine 6. 176 Improvements in serological testing include the CMV IgG avidity test. Avidity results (a numerical value) are informative despite lack of standardisation between the various manufacturers of the tests [eg. VIDAS, BioMerieux]. Low, intermediate and high values offer broadly useful information in defining recent (<3 months, low avidity) or past infection (>3 months, high avidity) 6, 8. However, not all past infections show high IgG avidity and not all recent infections show low avidity. Careful interpretation of avidity testing in conjunction with IgM and NAT testing of peripheral blood may identify primary CMV infection and offer a guide to timing of the infection (Table 1). The advent of NAT has certainly improved the detection of clinical infectious pathogens and is now increasingly being adopted by diagnostic laboratories. Polymerase chain reaction (PCR) is more sensitive, specific, cost-effective, less laborious and provides accurate and rapid diagnosis compared to conventional culture methods. Some laboratories can now screen clinical samples for CMV in blood, urine, amniotic fluid, newborn screening cards (NBSC) and autopsy materials. In addition, PCR can be adapted to test for various causative agents in one PCR reaction (multiplex PCR) 9. Prenatal diagnosis Routine antenatal screening for CMV during pregnancy is not performed in Australia but is performed as a matter of clinical judgment. Fetal abnormalities, if detected on ultrasound, may lead to maternal investigation with subsequent diagnosis of CMV. However, ultrasound is an insensitive method for detecting congenital CMV 10 and this technique has poor sensitivity. It has been claimed that ultrasound detects less than 5% of infected babies 11 and does not detect the subset of infected neonates with sensorineural hearing loss and other subtle late complications of congenital CMV. Nonetheless, ultrasound has the advantages of being non-invasive and can show structural and/or growth abnormalities. MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 In Focus After diagnosis of maternal infection, some pregnant women may desire fetal diagnosis (Table 2). Invasive techniques for diagnosing CMV include cordocentesis and amniocentesis. Cordocentesis is used in some centres for detection of CMV IgM antibody status, CMV PCR, liver enzymes, hematocrit and platelet count; however, analysis of amniotic fluid is probably the most appropriate for prenatal diagnosis 12, 13. Sampling of amniotic fluid for CMV testing is usually done between 21-22 weeks’ gestation 14, 15. This gestation has been selected as it may take 9 weeks for CMV to be excreted from the fetal kidneys and be detectable in the amniotic fluid. A positive CMV PCR of the amniotic fluid indicates fetal infection, although the association between infection and disease remains an area of uncertainty. Qualitative analysis of CMV in amniotic fluid is sensitive (92-98%) and specific (90-98%) 16. Some authors correlate worse outcomes with higher viral load in the amniotic fluid 17. A negative PCR result, generally an indicator of absence of CMV, may also be a false-negative result if the procedure is performed less than 6-9 weeks after maternal infection and/or before 21 weeks’ gestation. Diagnosis in the newborn The reference standard for diagnosing congenital CMV infection remains isolation of the virus from urine, saliva or plasma in the first 3 weeks of life. IgM positivity is indicative of congenital infection, but IgM antibodies are present in about 70% of infected babies 18. Beyond 3 weeks of life, tests can no longer differentiate congenital from perinatal infection. Infants suspected of CMV beyond the early neonatal period (especially for infants presenting with deafness) may have blood tested for CMV if blood has been routinely collected at birth and dried on a NBSC as part of a newborn screening programme. Retrospective diagnosis of congenital infection in infants presenting with later clinical illness and not to genetic causes is routinely performed by some laboratories 19, 20. Detection of CMV in blood at birth has been claimed to be as sensitive and specific as detection in urine 21, 22. NAT is used to detect the presence of CMV in maternal and infant urine, plasma and serum, along with fresh placenta, fresh umbilical cord and paraffin-embedded tissue, using CMV PCR. In addition, using in situ PCR, placenta and fetal tissue from CMV PCR positive liveborn and stillborn babies may be Table 1. Determining time of CMV infection. CMV IgM CMV IgG avidity • May remain positive for >2 years • If low infection, usually <3 months previous • Different assays with different sensitivities • May be high in recent infection (uncommon) • Some laboratories utilise two assays • If low in trimester 1 infection, may be pre-pregnancy • May inverse in recurrent infection • Retesting in 2-3 weeks may indicate kinetics of antibodies Table 2. Diagnosis of congenital CMV during pregnancy (fetal infection) and in infants. Fetal infection Neonate and older infection Serology CMV IgG pre-pregnancy + pregnancy scan if possible CMV IgG IgM IgM IgG avidity IgG avidity Amniocentesis Amniocentesis of >21 weeks’ gestational age (CMV viral load in amniotic fluid (high value suggests increased risk fetal infection) Molecular Maternal peripheral blood (NAT) Peripheral blood and urine (NAT) Placenta at birth (NAT) >21 days old, request testing of NBSC (NAT) M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 177 In Focus examined. This allows the determination of several factors: References the anatomical localisation of CMV in the placenta, addressing 1. Pass, R.F. et al. (2006) Congenital cytomegalovirus infection following first trimester maternal infection: symptoms at birth and outcome. J. Clin. Virol. 35, 216-220. 2. Munro, S.C. et al. (2005) Diagnosis of and screening for cytomegalovirus infection in pregnant women. J. Clin.Microbiol. 43, 4713-4718. 3. Rawlinson, W.D. (1999) Diagnosis of human cytomegalovirus infection and disease. Pathology 31, 109-115. specialised method that is not available to most pathology labs; 4. however, it is a sensitive method of addressing these issues Trincado, D.E. and Rawlinson, W.D. (2001) Congenital and perinatal infections with cytomegalovirus. J. Paediatr. Child Health 37, 187-192. 5. Stagno, S. et al. (1986) Primary cytomegalovirus infection in pregnancy. J. Am. Med. Assoc. 256, 1904-1908. 6. Lazzarotto, T. et al. (1997) Search for cytomegalovirus-specific immunoglobulin M: comparison between a new western blot, conventional western blot, and nine commercially available assays. Clin. Diag. Lab. Immunol. 4, 483-486. improving the prognosis of congenitally ill babies. 7. Ultimately, further tests and research are required to develop the Lazzarotto, T. et al. (2004) Congenital cytomegalovirus infection: recent advances in the diagnosis of maternal infection. Human Immunol. 65, 410415. 8. Munro, S.C. et al. (2005) Symptomatic infant characteristics of congenital cytomegalovirus disease in Australia. J. Paediatr. Child Health 41, 449-452. 9. McIver, C.J. et al. (2005) Development of multiplex PCRs for detection of common viral pathogens and agents of congenital infections. J. Clin. Microbiol. 43, 5102-5110. cellular tropism in vivo; the co-localisation of virus and tissue inflammation, informing if tissue damage is from viral mediated or immune mediated (possibly cytokines); and the sensitivity of histopathology for detecting viral infection. In situ PCR is a whilst providing details about viral transcription 23. These data are significant for further understanding the pathophysiology of CMV, providing correct diagnosis, directing therapies, and diagnostic test that predictively defines the outcome of a CMV infection during a woman’s pregnancy. In the meantime, use of multiple tests, with careful consideration of the results, allows us to provide useful information to mothers with infection during pregnancy and to parents of infected children. 10. Liesnard, C. et al. (2000) Prenatal diagnosis of congenital cytomegalovirus infection: prospective study of 237 pregnancies at risk. Obstet. Gynecol. 95, 881-888. 11. Ville, Y. (1998) The megalovirus. Ultrasound Obstet. Gynecol. 12, 151-153. 12. Lazzarotto, T. et al. (2000) Prenatal indicators of congenital cytomegalovirus infection. J. Pediatr. 137, 90-95. 13. Revello, M.G. et al. (1999) Quantification of human cytomegalovirus DNA in amniotic fluid of mothers of congenitally infected fetuses. J. Clin. Microbiol. 37, 3350-3352. 14. Azam, A.Z. et al. (2001) Prenatal diagnosis of congenital cytomegalovirus infection. Obstet. Gynecol. 97, 443-448. Preliminary Announcement Parasitology & Tropical Medicine MasterClass 2009 Clinical School – University of Tasmania, Hobart 6 – 7 March 2009 www.parasitologymasterclass.org A joint meeting of • ASM Parasitology and Tropical Medicine SIG; and •Australian College of Tropical Medicine (ATCM) Standing Committee on Medical Parasitology and Zoonoses The MasterClass will cover Introductory & Advanced Parasitology as well as topics related to tropical Medicine and will be suitable for Specialists & Trainees and Laboratory Scientists/Technicians in Infectious Diseases/Clinical Microbiology, Parasitology and Tropical Medicine and Haematology. The day and half program will include: • Expert Faculty •Practical Laboratory Workshops for Introductory & Advanced Parasitology •Half day Malaria Workshop incorporating seminars and hands-on laboratory sessions Chair: Richard Bradbury, University of Tasmania Co-Convenors: Dr Andrew Butcher – Microbiology and Infectious Diseases, SA Pathology Dr Harsha Sheorey – Microbiology, St Vincent’s Hospital, Melbourne Registration to open soon! Conference Organisers – Australian Society for Microbiology 178 15. Gouarin, S., et al. (2001) CMV gB genotypes and outcome of vertical transmission: study on dried blood spots of congenitally infected babies. J. Clin. Virol. 21, 75-79. 16. Enders, G. et al. (2001) Prenatal diagnosis of congenital cytomegalovirus infection in 189 pregnancies with known outcome. Prenat. Diagn. 21, 362377 17. Lanari, M. et al. (2006) Neonatal cytomegalovirus blood load and risk of sequelae in symptomatic and asymptomatic congenitally infected newborns. Pediatr. 117, e76-e83. 18. Revello, M.G. et al. (1999) Diagnostic and prognostic value of human cytomegalovirus load and IgM antibody in blood of congenitally infected newborns. J. Clin. Virol. 14, 57-66. 19. Barbi, M. et al. (2006) Neonatal screening for congenital cytomegalovirus infection and hearing loss. J. Clin. Virol. 35, 206-209. 20. Barbi, M. et al. (2000) Cytomegalovirus DNA detection in Guthrie cards: a powerful tool for diagnosing congenital infection. J. Clin. Virol. 17, 159-165. 21. Revello, M.G. and Gerna, G. (2002) Diagnosis and management of human cytomegalovirus infection in the mother, fetus and newborn infant. Clin. Microbiol. Rev. 15, 680-715. 22. Ross, S.A. and Boppana, S.B. (2005) Congenital cytomegalovirus infection: outcome and diagnosis. Sem. Pediatr. Infect. Dis. 16, 44-49. 23. Trincado, D.E. et al. (2005) Highly sensitive detection and localization of maternally acquired human cytomegalovirus in placental tissue by in situ polymerase chain reaction. J. Infect. Dis. 192, 650-657. Dr Jonathan Howard is a postdoctoral research officer at the Virology Division at SEALS and a conjoint lecturer at UNSW. He has worked on stillbirth and congenital infections for over 2 years. His interests are in the detection of pathogens associated with stillbirth and congenital infections. Beverley Hall is a registered nurse and midwife and works as a research nurse for the congenital infection study at the Virology Division at SEALS. Her interests are maternal, infant and fetal health. Professor William D Rawlinson – See Bio on page 172. MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope What happens when a baby dies: stillbirth investigations for infection and other aetiologies S Chaudry and TY Khong SA Pathology, Women’s and Children’s Hospital North Adelaide SA 5006 Email [email protected] AK Charles and AD Keil PathWest Laboratory Medicine, King Edward Memorial and Princess Margaret Hospitals, Subiaco WA 6008 Infections in stillbirths are common, often clinically silent and need to be screened. The microbiology laboratory needs to have the appropriate culture techniques and expertise. The results of the clinical features, the pathology findings of the fetus and the placenta and the microbiological and serological features need to be interpreted together; individual results should not be considered in isolation. intrauterine infections. There is an association with older women, obesity and infertility treatment that are factors likely to be increasing the rate of stillbirths. Other common factors associated with stillbirth include placental disorders (e.g. placental abruption and vascular under-perfusion), complications of multiple gestation, and umbilical cord abnormalities or accidents. Several factors may coexist in individual cases. In approximately 15-25% of stillbirths no cause is identified. Stillbirth is defined in Australia as the loss of a fetus who shows no signs of life at birth and is at least 400 grams in birth weight or at least 20 weeks’ gestation. In Australia in 2005, there were 1,979 reported fetal deaths, at a rate of 7.3 per 1,000 births, about 19% of which are at term, making stillbirth a far more common condition than SIDS 1. Infection, which may involve mother, fetus or placenta, is associated with 10-25% of stillbirths in developed countries; it is a more frequent cause of stillbirth in developing countries 2. Infection may cause stillbirth by a number of mechanisms including direct infection, placental damage, and indirect mechanisms without identifying infection of the fetus or placenta or severe maternal illness. Assigning a specific infection as a cause of death may not be straightforward. Firstly, stillbirths may have multiple causes and infection may be one of them. Secondly, in an already compromised fetus due to maternal or fetal cause, infection may accentuate or precipitate the demise. Thirdly, despite finding a specific organism on culture or serological evidence of recent infection, these agents may not be the actual cause of death. The earlier (in gestation) the stillbirth, the more likely it will be associated with infection. It is not clear why ascending infection is so common in midtrimester. Stillbirth has been a hidden medical issue but has an immense effect on the woman as well as family members, physicians and nurses. It may be a potential marker of maternal or inherited disease but, despite this, it is an area that is under investigated. This paper sets out the investigations that may explain the cause of death and which may be valuable in counselling parents about recurrence risk in subsequent pregnancies, with an emphasis on information regarding the infectious aetiology of stillbirth. Currently, the principal risk factors and causes of stillbirth in developed countries are congenital anomalies, preeclampsiarelated complications, intrauterine growth restriction and M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 The important clinical point is that fetal and placental infection is often clinically silent, and therefore each stillbirth needs to be 179 Under the Microscope investigated with infection in mind, especially the non-macerated cases. Around 70% of all acute chorioamnionitis is clinically silent. Chorioamnionitis can also present with bleeding and abdominal pain like abruption or be associated with premature prelabour rupture of membranes and so, even if symptomatic, may not be recognised. Most of the patients with histological chorioamnionitis have no maternal symptoms such as fever, uterine tenderness or maternal leukocytic response. There are two major microorganism-related mechanisms associated with significant perinatal mortality and morbidity. First, ascending genital tract infection, almost always bacterial, which ranges from localised choriodecidual inflammation to frank chorioamnionitis with fetal sepsis; this is a major cause of mid trimester miscarriage and severe preterm delivery (Figure 1). Second, haematogenous spread of maternal systemic infection, be it bacterial, viral or parasitic 3. Organisms mostly associated with ascending infection are the genital mycoplasma species Ureaplasma urealyticum and Mycoplasma hominis, but a large variety of bacteria can colonise the female genital tract without causing any symptoms in pregnant woman. Listeria infects by the haematogenous route and is readily identified culturally and by special stains; it leads to abscess formation in the placenta and is one of the definitive causes of stillbirth 4. In case of parasitic infection, as in malaria, it is not uncommon to find parasitaemia in intervillous spaces of the placenta of infected mothers with uninfected fetal blood. Toxoplasmosis is a worldwide zoonosis. Fetal infections result from parasitic disease of placenta that can destroy the fetus or lead to varying degrees of fetal/congenital infection. The organism can be detected by placental tissue or body fluid culture and specific polymerase chain reaction (PCR) testing of these samples. However, the overall contribution of toxoplasma to fetal death is relatively small. Stillbirths or neonatal deaths occur in 5% of pregnancies with first trimester toxoplasmosis, in 2% with second trimester infection and in 0% in third trimester infection 5. Although it is clear that viruses can cause stillbirth, the overall nature of this relationship is unclear. Serological or PCR evidence of an infection does not prove causation. Parvovirus B19 (Figure 2) appears to have strongest association with stillbirth as it can either infect fetal erythropoietic tissue – leading to severe fetal anaemia and/or hydrops, both potential mechanisms for fetal death – or infect myocytes – leading to myocarditis and in utero heart failure. The risk of stillbirth is greater for parvovirus infection occurring prior to 20 weeks’ gestation 6. Enteroviruses, including Coxsackie A and B, echoviruses and other enteroviruses are also associated with stillbirth. Coxsackie viruses can cross the placenta and cause villous necrosis, inflammatory cell infiltration, calcific pancarditis and hydrops. Cytomegalovirus (CMV) is one of the common congenital infections and placental involvement is well documented. The virus can be detected through serology and culture/PCR but the exact mechanism of how CMV causes stillbirth is not clear. Rubella virus can cause endothelial damage and thrombosis in placental and fetal vessels, leading to stillbirth. The risk to the fetus is greater at early gestation and decreases with increased gestational age. However, with the development of rubella vaccine and its widespread adoption, this virus has little contribution in stillbirths in developed countries. Syphilis is one of the major causes of adverse pregnancy outcomes in developing countries and high rates are reported in parts of rural Australia. With primary and secondary syphilis, stillbirth, neonatal death or prematurity occurred in 50% of cases, whereas with early latent or late syphilis, stillbirths occurred in only 10% 5. Figure 1a. Acute chorioamnionitis. 180 Figure 1b. Funisitis, with margination and infiltration of neutrophils through the venous wall of the umbilical cord into the stroma. MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope Outside the context of infectious aetiologies of stillbirth, the autopsy could reveal other causes of death. Careful external examination and measurements could reveal growth restriction as an associated finding of stillbirth. Other causes obvious on external examination are hydrops fetalis (which may have an infectious aetiology), congenital malformations, such as skeletal dysplasias, or karyotypic anomalies, such as trisomy 18 or triploidy. Internal examination could reveal numerous congenital malformations or corroborative evidence of growth restriction. Uteroplacental vascular insufficiency, often associated with maternal hypertensive disorders of pregnancy, and placental abruption could be confirmed by placental examination. Figure 2. Parvovirus inclusion in an early pregnancy placental villus. Protocols for investigation of stillbirth It is important to have a set of rules or protocols to investigate stillbirths. Almost all protocols follow the same set of investigations. It is important that the microbiology laboratory is set up for the investigation of stillbirths and is able to culture both for the unusual and more fastidious organisms such as genital mycoplasma and Haemophilus species. The fetus is often delivered through the vagina and exposed to A microbiological examination must be taken – swabs from lung, stomach and liver for microbiological cultures. Group B Streptococcus (GBS), Escherichia coli and Ureaplasma urealyticum are the organisms commonly associated with chorioamnionitis and fetal infection. Stillborn infant blood (cord blood or, if this is not possible, infant cardiac blood) is collected for microbial cultures of GBS, Haemophilus species, Listeria and/ or coliforms. Maternal serology testing of syphilis, parvovirus, toxoplasmosis, rubella, herpes simplex virus (HSV) and CMV, as well as specific PCR testing of fetal tissues can be done. Mycobacterium testing is of interest if TB is suspected or the cause of death is not obvious. In ambiguous situations, elevated fetal serum b2 microglobulins can be used as a reliable marker for intrauterine infection due to CMV or toxoplasmosis 9. the vaginal flora, and it is easy for fluid to be moved as the If consent not given fetal chest and abdomen are compressed, and for bacterial If consent is not given, a limited fetal evaluation should be discussed with parents who are resistant to a complete autopsy. However, there is no adequate substitute for a full fetal autopsy. Some less invasive alternatives that are acceptable by parents are MRI, needle biopsy of tissue and the non-invasive component of the standard autopsy such as external fetal examination and placental examination (see below). contamination to occur. Bacterial overgrowth is particularly common after a prolonged delay from delivery until post mortem. The interpretation of the microbiology results is ideally a communication between the clinician, the perinatal pathologist and the clinical microbiologist. Full autopsy The most important part of the workup of a fetal demise is the autopsy of the fetus. The decision to proceed with an autopsy must be made by the parents and informed consent is necessary. The healthcare providers should strongly emphasise that the Placental examination Culture Subamniotic swabs for at least aerobic and, ideally, anaerobic cultures including for bacterial vaginosis-associated organisms result of the autopsy may be useful to the patient and her family in planning future pregnancies. However, despite the autopsy, cause of death may remain undetermined in 12-50% of cases 7. If consent given The standard fetal autopsy includes a comprehensive external examination, photography and radiography of the fetus and gross and histological and supplementary laboratory investigations such as microbiological, cytogenetic and metabolic studies 8. Examination of the internal organs (weights, detailed macroscopic and histological examination) should also be carried out. There should also be examination of the placenta and umbilical cord (Figure 3) with cultures if unable to be taken from the fetus. M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 Figure 3. Candida colonies on surface of umbilical cord on careful inspection. 181 Under the Microscope if resources are available, are recommended for all cases. Fresh placental tissue is collected for tissue culture if infection is suspected (GBS, Listeria, Haemophilus, coliforms and viruses). If TB is suspected, a separate sample is collected for mycobacteria. Cytogenetics Atay et al. showed that histopathological chorioamnionitis and placental culture positivity rates in control and study group were 64.7% vs 0%. Bacteria were recovered from 90.9% of placentas and 36.4% of fetal lungs of the cases with histopathological chorioamnionitis 10. Pankuch et al. showed that bacteria were recovered from 72% of placentas with histological chorioamnionitis and from 82% of clinical chorioamnionitis, all of which had histological chorioamnionitis. Nearly 50% bacteria recovered from placentas were anaerobes 11. Viral cultures and serology are often not available or are of relatively low sensitivity. The microorganisms most commonly recovered from the chorioamnion include Ureaplasma urealyticum, facultative and anaerobic Gram-positive cocci, Gardnerella vaginalis and Bacteroides species. Haemophilus influenzae (usually nontypable), Neisseria gonorrhoeae and Chlamydia trachomatis are rarely recovered from placentas 12. Clinical history Histopathological examination Histological acute chorioamnionitis (Figure 1) is defined as a maternal neutrophilic response to bacterial infection with or without an accompanying fetal neutrophilic response. Acute chorioamnionitis is usually the result of infection in the female genital tract. Other less common routes are haematogenous seeding of placenta and contiguous spread of organisms from adjacent pelvic viscera. Fetal inflammatory response does not necessarily mean fetal infection; it is an indication of activation of fetal immune system. Immune activation in turn leads to increased levels of cytokines in fetal blood that are associated with increased risk of brain injury and chronic lung disease. Histopathological examination of placenta contributes to a better understanding of the cause of intrauterine fetal death. Rayburn et al. showed that significant histological aberrations were found in placentas of 98% cases. The most frequent abnormalities were those of vascular insufficiency, haemorrhagic endovasculitis, retroplacental haematoma, acute chorioamnionitis with fetal involvement, and erythroblastosis/ hydrops 13. Mayo et al. showed that histological chorioamnionitis occurred in 2.6 times more often in women with stillbirths than in women with live births 14. Chorioamnionitis with acute villitis is seen with fetal bacterial sepsis especially by streptococci and Gram-negative bacilli. The presence of mixed lympho-histiocytic infiltrate in the terminal villous stroma is the feature of chronic villitis (Figure 4). Chronic villitis is usually associated with placental infection with CMV, syphilis or toxoplasma. Less common agents like HSV and coxsackie viruses are occasionally associated with chronic villitis. Less virulent organisms such as the genital mycoplasma species cause asymptomatic maternal infection; however, they are associated with histological chorioamnionitis and adverse pregnancy outcome. 182 Where relevant, if karyotyping has not been done, then placental tissue can be used for cytogenetics studies. Maternal investigations When stillbirth and neonatal death occurs, the obstetric history, including exposure (e.g. medications and viral infections), history of amniocentesis, intrauterine contraceptive device and family history with three generation pedigree, if possible, should be reviewed. Maternal history of fever, abdominal pain or other evidence of lower genital tract infection such as offensive vaginal discharge should also be recorded. Consideration of performing an antenatal ultrasound scan prior to stillborn delivery is recommended by most protocols (whenever possible, following confirmation of stillbirth) for the identification of unknown abnormalities. The ultrasound findings may be helpful when the family does not consent to a full autopsy 15. Gram-staining and fibronectin test should be carried out on vaginal or cervical secretions. A positive test is strongly associated with chorioamnionitis and neonatal sepsis 16. Also, at the time of stillbirth confirmation and prior to delivery, collection of amniotic fluid by amniocentesis is recommended. This results in good microbiological specimens and material for cytogenetic analysis. It may be screened for leukocyte count, Gram-stain, pH, glucose concentration, endotoxin, lactoferrin, cytokine levels (e.g. interleukin-6). The cytokines commonly quantified in either the amniotic fluid or the blood include interleukin-6, TNF alpha, interleukin-8. Further, PCR testing can be used to identify agents such as human immunodeficiency virus, CMV, HSV, parvovirus B19, toxoplasmosis and bacterial DNA in amniotic fluid. Screening for GBS carriage should be done by combined vaginal/rectal swabs and a white blood cell (WBC) count done in maternal blood. Serology tests for parvovirus B19, toxoplasmosis, CMV, syphilis, rubella, HSV and HIV are recommended as core investigations. Maternal blood cultures should be taken if the Figure 4. Chronic villitis: chronic inflammatory cells in the stroma of a terminal villus. MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope clinical findings suggest active chorioamnionitis, with additional cultures being performed when indicated (e.g. faeces for Listeria and campylobacter infection). Conclusion High vaginal/low vaginal swabs (HVS/LVS) should also be taken. There is an association between bacterial vaginosis and premature labour but antenatal management of bacterial vaginosis as a means of preventing premature labour remains controversial. Possible further research would include serum concentrations of interleukin-6, interleukin-8 and tumour necrosis factor, and noncytokine markers of infection, including serum C-reactive protein and serum ferritin. with close collaboration of all involved specialists in the Interpretation Acute chorioamnionitis is considered to have virtually always an infective aetiology, even though bacteria are only cultured in some of the cases. This discrepancy may be due to maternal antibiotic administration, failure to culture for implicated organisms such as the genital mycoplasma species or bacterial vaginosis-associated organisms, or the reporting of potentially pathogenic organisms as ‘normal’ flora with no further specification. A fresh stillbirth with no evidence of chorioamnionitis does not exclude an infectious aetiology. Organisms such as GBS can cause fetal infection with intact membranes. The infection may be overwhelming, with insufficient time to initiate an inflammatory reaction. Furthermore, there may be no inflammatory response at autopsy as the cellular immune system in an extremely premature fetus may be immature. In a fresh stillbirth with evidence of chorioamnionitis, the possibility of isolation of organism from fetal tissue or placenta is always high (with the caveats mentioned earlier) and an infectious cause must be considered. Caution is advised in the interpretation of organisms cultured in these scenarios as being either ‘vaginal contaminants’ or normal flora, since they may, in fact, be very significant. In cases of macerated stillbirths, the presence of chorioamnionitis does not necessarily mean infection unless a fetal reaction is identified. In a macerated stillbirth where there is no evidence of chorioamnionitis and no organism isolated, other causes of stillbirth should be considered. Most macerated stillbirths appear to have a low yield of identification of a causative bacterial agent, although syphilis and viral causes may be found. In practice, every non-macerated, and not obviously dysmorphic fetus should have bacterial cultures taken and assessed in the light of histology. Viral infections should be considered in growth restriction and in stillbirths with rashes, localised areas of necrosis (e.g. liver) and hydrops in both macerated and nonmacerated stillbirths. Infections remain a frequent factor in stillbirths and are often clinically silent. Stillbirths require active screening for infections interpretation of results. References 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. Elizabeth Sullivan, AIHW National Perinatal Statistics Unit [personal communication]. Goldenberg, R.L. et al. (2004). Stillbirth: a review. J. Matern. Fetal. Neonatal. Med. 16, 79-94. Al-Adnani, M. and Sebire, N.J. (2007) The role of perinatal pathological examination in subclinical infection in obstetrics. Best Pract. Res. Clin. Obstet. Gynecol. 21, 505-521. Benirschke, K. and Robb, J.A. (1987) Infectious causes of fetal death. Clin. Obstet. Gynecol. 30, 284-294. Gibbs, R.S. (2002) The origins of stillbirth: infectious diseases. Semin. Perinatol. 26, 75-78. Enders, M. et al. (2004) Fetal morbidity and mortality after acute human parvovirus B19 infection in pregnancy: prospective evaluation of 1018 cases. Prenat. Diagn. 24, 513-518. Fretts, R.C. (2005) Etiology and prevention of stillbirth. Am. J. Obstet. Gynecol. 193, 1923-1935. ACOG Committee Opinion No. 383 (2007) Evaluation of stillbirths and neonatal deaths. Obstet. Gynecol. 110, 963-966. Dreux, S. et al. (2006) Fetal beta2-microglobulin as a marker for fetal infectious diseases. Prenat. Diagn. 26, 471-474. Atay, G. et al. (2004) The possible role of intrauterine infections in unexplained second trimester abortions and macerated stillbirths: a study from a single center. J. Perinatol. 24, 679-685. Pankuch, G.A. et al. (1984) Placental microbiology and histology and the pathogenesis of chorioamninitis. Obstet. Gynecol. 64, 802-806. Hillier, S.L. et al. (1991) Microbiological causes and neonatal outcomes associated with chorioamnion infection. Am. J. Obstet. Gynecol. 165, 955-961. Rayburn, W. et al. (1985) The stillborn fetus: placental histological examination in determining a cause. Obstet. Gynecol. 65, 637-641. Moyo, S.R. et al. (1996) Stillbirths and intrauterine infection, histologic chorioamnionitis and microbiological findings. Int. J. Gynecol. Obstet. 54, 115123. Protocol for Stillbirth Investigation. Alberta Heritage Foundation for Medical Research. October 2005. Goldenberg, R.L. et al. (2000) Intrauterine infection and preterm delivery. N. Engl. J. Med. 18, 1500-1507. Sadia Chaudry is a paediatrician, having received her fellowship training from the College of Physicians and Surgeons Pakistan (CPSP). She is currently a registrar in paediatrics at the Women’s and Children Hospital. Her research interests range from investigating infective causes of stillbirths to diseases of the neonates. Adrian Charles is a paediatric and perinatal pathologist who trained in the UK and has been in Perth since 1999. His research interests are in placental development, intrauterine infection/inflammation and paediatric tumours. Tony Keil is a medical microbiologist and head of the Department of Microbiology at Princess Margaret Hospital for Children and King Edward Memorial Hospital for Women. He and his scientific staff work in close collaboration with perinatal pathology colleagues in elucidating infective causes of stillbirths. Yee Khong is a perinatal and obstetric pathologist who trained in the UK and has been in Adelaide since 1991. His research interests are in placental and obstetric pathology. Membership Be part of the ASM – become a member – www.theasm.com.au M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 183 Under the Microscope When a baby dies: stillbirth from the community perspective and what parents want to know Emma Kirkwood Ros Richardson Stillbirth Foundation Australia Level 18, 55 Market Street Sydney NSW 2000 Tel 0419 995 464 Email emma@stillbirthfoundation. org.au SIDS and Kids NSW PO Box 431 Camperdown NSW 1450 Tel (02) 8585 8702 Fax (02) 9818 4555 Email [email protected] The death of a child at any time is a devastating experience for parents, with lifelong physical, psychological and spiritual sequelae. The death of a baby before birth presents its own particular challenges. This article is written by mothers whose babies have died. Our daughters, Olivia and Annie Rose, were stillborn at 36 weeks after uneventful pregnancies 15 years apart. In this article we describe the reality of stillbirth expressed by parents in sadness over their lost hopes and dreams and in the loss of a social identity that would validate the individuality and significance of those little lives. Over the last 10 years, we applaud the improvement in and the more humanised approach to the care of stillborn babies and their parents; however, concern now exists around the levels of awareness about stillbirth in the community, before, during and after any pregnancy. “I’m sorry but your baby has died” are the hardest words for any parent to hear. With stillbirth, these words introduce parents to a death and grief that is not well understood and is poorly accepted by the community. Stillbirth is emotionally complex, with long lasting symptoms of grief and significant struggles to find meaning 1. Stillbirth is an event that happens often completely unexpectedly to a happy couple, who then commence a journey travelled without consistency of care that is typically far removed from any previous life experience. In such circumstances, much information and support is needed from the medical community, family and friends. In Australia, one in every 140 babies is stillborn; in the scheme of things, stillbirth is a relatively common form of death (Table 1) 2,3. In an age of enormous medical and technical advances, it is surprising that the number of stillborn babies has not reduced over the last decade. We live in an age of great technology and information; however, stillbirth remains an event cloaked in mystery. In most cases, the first time a family hears of stillbirth is when it happens to them. 184 A plethora of extreme emotions is felt at the time a baby dies – incomprehension, disbelief, intense sadness, crying, anger, anxiety, guilt, loneliness, fear, grief, love, joy and pride. The emotional and physical shock and trauma associated with stillbirth requires personal sensitive care. It is a confusing time; not only does one mourn the death of their baby and ask why did their baby die, but parents will also wonder and marvel at the child they have created. Parents need privacy and information. There are many considerations, including what they will experience during the birth, pain, blood loss, lactation, along with guidance and information about seeing their baby, registering the birth, planning the funeral, as well as life beyond this time. The first time parents meet their baby, he or she is dead; this may be the first time they see a dead person. Parents may feel frightened about how their baby will look 4 and may find it challenging to accept that their baby has really died. They may need assistance in both facing and separating from their baby 5. Although the value of parents seeing their stillborn baby is still debated, the choice is for the family to make. Table 1. Deaths in Australia 2005 2,3. Number Cause of death in Australia 2946 Men died from prostate cancer 2736 Adults died from breast cancer 1979 Babies were stillborn 1273 People died from skin melanoma 884 Women died from ovarian cancer 87 Babies died from SIDS MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope Stillborn babies are born into a void of silence and into the love and desperate longing of their parents. Parents love their stillborn baby as they do their other children. Yet a stillborn baby, and to an extent its family, is defined by the word stillbirth which in itself can bring a conversation to an abrupt halt. Parents must learn to live with their loss in a society that defines the value of a person through life. Many bereaved families, and in particular mothers, struggle with this for many years. Despite the fact that stillborn babies do not breathe, their existence is very real to their parents, who are left with unfulfilled plans, hopes and dreams for their future lives. For many parents, creating an identity around their child and gathering mementos of their brief time together is enormously important. Whilst there have been great advances in the care of stillborn babies and their families over the last 20 years, consistency of care remains an issue today. The care received by families whose baby is stillborn varies greatly between hospitals and staff, and is dependent on the skill, experience and empathy of the caregivers. Caregivers need to support parents in moments of chaos and at other difficult times 5, while knowing that their every action and piece of advice will be remembered in clear and accurate detail by the parents. Caring for families who have experienced the stillbirth of their baby is challenging and demanding for the medical 6, nursing and allied staff. Once trust is established, parents value the guidance of caregivers. Many parents speak fondly of the facilitated care and support they received during the precious time spent with their stillborn baby and will forever treasure this memory. There is no fear, just love and a desperate longing to cherish and get to know this beautiful person. The short period of time spent with their baby must give opportunity and allow for every detail to be etched in each parent’s heart and mind. To have the opportunity to collect mementoes, such as locks of hair, footprints and handprints, take photographs and to bathe, dress, wrap, kiss, and introduce him or her to family and friends is important for many bereaved families. Loneliness and isolation are two very great emotions that parents of stillborn babies experience, along with intense pain and sadness. These are felt at the time of the birth and thereafter, with some parents forever reporting a sense of isolation. Whilst there is no evidence from randomised controlled trials that there is or is not a benefit from providing specific psychological support or counselling after perinatal death 7, meeting with others is anecdotally beneficial for many families. Death is not accepted well or wholly in today’s western society, and the death of a baby is even more challenging for family and friends, particularly if that death is unexplained. Condolences and suggestions that it is “God’s will” or “not the right time” are not supportive for the grieving family. Parents need to be able to normalise and comprehend their grief and loss, and the task of educating friends and colleagues about stillbirth is an additional and unfair stress. The best way to describe stillbirth and to make it real has not yet been elucidated or promoted. Perhaps the use of the more accurate term, “deadbirth”, coined by an 8 year old boy when describing his little sister to his friends, is more informative and honest. M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 At the time of their baby’s birth, families wish to know why their baby died and most will desire to save others from living the same tragedy. For many families, the cause of their stillborn baby’s death will never be determined, despite a full post mortem investigation. Consenting to an investigation of their baby’s body is unthinkable for many parents and the guidance and expertise of senior, knowledgeable carers is required. Any decision made at the time of a baby’s death is challenging; even normal everyday decisions are not easy such as when to take a shower, have a drink or eat! Therefore, the monumental decision to allow investigations on their baby can only be made with the provision of accurate, honest information about every aspect of post mortem. All examinations of a baby’s body must be conducted with dignity and respect of both the baby and the parent’s values. Results must be provided in a timely and sensitive manner to parents. Today, the collective community does not know, yet should, what families learn at the time of their baby’s death. The facts about stillbirth, including the incidence and what is being done to reduce it, as well as risk factors and support services available, are important public health messages. The death of a baby is a massive life changing event and parents, along with health professionals, must work together to reduce the stigma of stillbirth. It is not a scary word. For us, stillbirth describes two very real, beautiful and beloved little girls who have entirely shaped our lives and those of many others. References 1. Cacciatore, J. and Bushfield, S. (2007) Stillbirth: the mother’s experience and implications for improving care. J. Soc. Work End Life Palliat. Care 3, 59-79. 2. Australian Bureau of Statistics – Causes of Death (2005). 3. AIHW National Perinatal Statistics Report (2005). 4. Saflund, K. and Wredling, R. (2006) Differences within couples’ experience of their hospital care and well-being three months after experiencing a stillbirth. Acta Obstet. Gynecol. Scand. 85, 1193-1199. 5. Saflund, K. et al. (2004) The role of caregivers after a stillbirth: views and experiences of parents. Birth 31, 132-137. 6. Gold, K.J. et al. (2008) How physicians cope with stillbirth or neonatal death: a national survey of obstetricians. Obstet. Gynecol. 112, 29-34. 7. UK National Health Service’s Palliative and Supportive Care website (http:// www.library.nhs.uk/palliative/ViewResource.aspx?resID=126800). Guidelines for Clinicians: Perinatal Mortality Audit Guideline incorporating Psychological and Social Aspects of Perinatal Bereavement can be found at http://www.psanzpnmsig.org/guideline.html Emma Kirkwood’s second child, her first daughter, Olivia, died unexpectedly in utero and was born on 31 July 2002. At the time, Emma was amazed and disturbed to discover that little funds were being spent on stillbirth research and therefore resigned from employment within the pharmaceutical industry to establish the Stillbirth Foundation in 2005. Today, on an entirely voluntary basis, Emma runs the Stillbirth Foundation which operates to reduce the incidence of stillbirth in Australia through funding in addition to encouraging research into stillbirth and increasing public awareness about stillbirth. Ros Richardson is the General Manager of SIDS and Kids NSW. Ros is a bereaved parent and has a background in nursing and public health. Her service provides support for families who experience the death of their baby or child during pregnancy, birth and infancy. Ros has particular interest in access to care and support for bereaved families, and in increasing awareness and preventative public health campaigns in perinatal and infant death. 185 Under the Microscope Longer-term outcomes of infections in pregnancy: pathogenesis of diabetes and other chronic infections Maria E Craig Virology Research, POWH and UNSW Research Laboratories, South Eastern Area Laboratory Services, Prince of Wales Hospital, Randwick NSW Kin-Chuen Leung Virology Research, POWH and UNSW Research Laboratories, South Eastern Area Laboratory Services, Prince of Wales Hospital, Randwick NSW School of Women’s and Children’s Health, University of New South Wales, NSW Institute of Endocrinology and Diabetes, The Children’s Hospital at Westmead, NSW Faculty of Medicine, University of New South Wales, NSW Discipline of Paediatrics and Child Health, University of Sydney, NSW Department of Paediatrics, St George Hospital, Gray St Kogarah NSW 2217 Tel 02 9113 3637 Fax 02 9113 3810 Email [email protected] Rubella and cytomegalovirus (CMV) are recognised causes of congenital diabetes. The role of in utero infection with other viruses, such as enteroviruses (EV), in the development of childhood diabetes is less clear. Epidemiological studies have demonstrated an association between maternal EV infection and subsequent development of type 1 diabetes in their offspring, suggesting that the disease process begins in utero. Congenital infection with viruses such as Rubella and CMV may result in severe long-term sequelae, including developmental delay, hearing loss, cerebral palsy, epilepsy and diabetes 1. CMV is the most common cause of viral-induced congenital malformation – primary CMV infections occur in up to 2% of pregnant women, with 30-40% of mothers vertically transmitting the virus to the fetus. The virus may be transmitted in utero during primary maternal infection, or by reactivation or reinfection of seropositive mothers. While most (85-90%) of congenital CMV cases are asymptomatic at birth, 10-15% will develop symptoms in later life, the most common being sensorineural hearing loss. Infection with rubella virus during the first 12 weeks of pregnancy results in congenital infection and/or miscarriage in 80-90% of cases. The congenital rubella syndrome involves multiple organ systems, with a long period of active infection and virus shedding in the postnatal period. The syndrome includes a range of malformations, including sensorineural deafness, cataracts, cardiac anomalies and mental retardation, with late complications including diabetes, thyroid disease, growth hormone deficiency, and progressive panencephalitis. Congenital forms of virus induced diabetes result from direct infection of the pancreatic ß-cells which may be chronic. Certain viruses are known to be pancreotropic, including mumps 2, rubella 3 and picornaviruses 4. In the case of congenital rubella ASM NEW MEMBERS New South Wales Queensland South Australia Duncan Rouch Suzanne Payne Julia Muenchhoff Lisa Atherton Barbara Pearce Rebecca Goulter Aaron Sim Jodie Spink Jessica Cheung William Smith Sanmarie Schlebusch Katherine Cantlon Mayda Alexandrides Sarah Fry Stuart Mckessar Sheena McGowan NT Mark Mayo 186 Victoria Lee Hudek Western Australia Paul Ingram Cameron Truarn Wei Liang Ng MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope syndrome, overt disease can develop after more than 20 years following in utero infection 3. Congenital CMV infection is also thought to result in late development of diabetes 5. In these relatively uncommon cases, the process is probably due to gradual ß-cell destruction rather than an autoimmune process. However, an association was found between CMV infection and islet cell antibodies in patients with newly diagnosed diabetes 6, suggesting that persistent CMV infection (but not necessarily congenital) can lead to autoimmune diabetes. The majority of children who develop diabetes have type 1 (insulin dependent) diabetes, a condition that affects approximately 1 in 700 children aged <15 years. This is an autoimmune disease caused by destruction of the insulin producing ß-cells in the pancreas, which is probably mediated by autoreactive T-cells. The risk of developing type 1 diabetes is to some extent genetically determined, but environmental factors also appear to be involved in the autoimmune process. Indeed, the rapid increase in the incidence of type 1 diabetes during recent years, particularly in Australia 7, 8, is highly supportive of a major role for environmental factors in the disease process. EVs, in particular Coxsackie virus B4 (CVB4), are the most widely studied and likely environmental triggers of ß-cell autoimmunity and type 1 diabetes. Higher rates of enterovirus infection have been demonstrated in children at onset of type 1 diabetes, in particular amongst those who do not have diabetes associated risk genes 9. An increased number of enterovirus infections have been found in pre-diabetic children in several prospective studies using serological tests and enterovirus RNA detection 10. Enterovirus infections during pregnancy have also been associated with an increased risk of developing type 1 diabetes in the offspring 11, suggesting that the autoimmune process may begin in utero. Whilst most studies imply a causal association of enterovirus infection and type 1 diabetes, there are also several studies demonstrating direct infection of ß-cells in humans with type 1 diabetes 4, 12. 2. Helmke, K. et al. (1986) Islet cell antibodies and the development of diabetes mellitus in relation to mumps infection and mumps vaccination. Diabetologia 29, 30-33. 3. Forrest, J.M. et al. (1971) High frequency of diabetes mellitus in young adults with congenital rubella. Lancet 2, 332-334. 4. Yoon, J.W. et al. (1979) Isolation of a virus from the pancreas of a child with diabetic ketoacidosis. NEJM 300, 1173-1179. 5. Ward, K.P. et al. (1979) Congenital cytomegalovirus infection and diabetes. Lancet 1, 497. 6. Pak, C.Y. et al. (1988) Association of cytomegalovirus infection with autoimmune type 1 diabetes. Lancet 2, 1-4. 7. Taplin, C.E. et al. (2005) The rising incidence of childhood type 1 diabetes in New South Wales, 1990-2002. Med. J. Aust. 183, 243-246. 8. Chong, J.W. et al. (2007) Marked increase in type 1 diabetes mellitus incidence in children aged 0-14 yr in Victoria, Australia, from 1999 to 2002. Pediatr. Diabetes 8, 67-73. 9. Craig, M.E. et al. (2003) Reduced frequency of HLA DRB1*03-DQB1*02 in children with type 1 diabetes associated with enterovirus RNA. J. Infect. Dis. 187, 1562-1570. 10. Lonnrot, M. et al. (2000) Enterovirus RNA in serum is a risk factor for beta-cell autoimmunity and clinical type 1 diabetes: a prospective study. J. Med. Virol. 61, 214-220. 11. Dahlquist, G.G. et al. (1995) Maternal enteroviral infection during pregnancy as a risk factor for childhood IDDM. A population-based case-control study. Diabetes 44, 408-413. 12. Dotta, F. et al. (2007) Coxsackie B4 virus infection of beta cells and natural killer cell insulitis in recent-onset type 1 diabetic patients. Proc. Natl. Acad. Sci. USA 104, 5115-5120. Dr Maria Craig is a senior lecturer in the School of Women’s and Children’s Health, University of New South Wales and conjoint senior lecturer, Discipline of Paediatrics and Child Health, University of Sydney. Her research interests include epidemiology of childhood diabetes and the role of enterovirus infections in diabetes pathogenesis. Dr Kin-Chuen Leung is a senior hospital scientist in the Virology Research Laboratory, POWH and conjunct senior lecturer in the Faculty of Medicine, University of New South Wales. His research interests include pathogenesis of autoimmune diabetes and cellular models of enterovirus infection. Several mechanisms for the induction of ß-cell destruction by viruses have been suggested. Viruses may also cause a direct cytolysis of infected ß-cells or induce bystander activation of autoreactive T-cells due to the inflammatory mediators released in infected islets, or alternatively the process may be due to molecular mimicry, whereby viral antigens cross react with ß-cell antigens and induce autoreactivity. Whilst there is currently limited evidence that enterovirus infection in utero is an important cause of childhood onset diabetes, prospective studies of infants at genetic risk of type 1 diabetes, such as the international studies TRIGR, DAISY and TEDDY, and the VIGR study in NSW, may help to address the role of virus infections early in life. References 1. Munro, S.C. et al. (2005) Symptomatic infant characteristics of congenital cytomegalovirus disease in Australia. J. Paediatr. Child Health 41, 449-452. M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 187 Under the Microscope Toxoplasmosis in pregnancy: often suspected, rarely convicted Clinical manifestations and presentation Toxoplasmosis is usually asymptomatic or causes non-specific, self-limiting illness with malaise, mild fever and lymphadenopathy Lyn Gilbert (commonly cervical). Severe, multi-system disease can occur in Centre for Infectious Diseases and Microbiology Institute of Clinical Pathology and Medical Research Westmead Hospital Westmead NSW 2145 Tel 61 2 9845 6252 Fax 61 2 9893 8659 Email [email protected] severely immunodeficient individuals. If toxoplasmosis occurs during pregnancy, the immunologically immature fetus is at risk. Maternal toxoplasmosis is often suspected because of symptoms or a positive toxoplasma IgM which often persists for months or years after acute infection. At least 80% of intrauterine infections are asymptomatic and often unrecognised. Gross clinical features of fetal/congenital toxoplasmosis – hepatosplenomegaly, hydrocephalus liver and/ Toxoplasmosis during pregnancy is uncommon and usually asymptomatic but can cause catastrophic fetal disease. It is often suspected because of non-specific symptoms or positive serological tests. However, false-positive toxoplasma IgM tests are common and confirmatory tests not always reliable. The risk of fetal infection increases as pregnancy progresses; it should be diagnosed or excluded by amniotic fluid PCR, especially early in pregnancy when the risk of severe damage is high. Prompt antibiotic therapy of maternal infection probably reduces fetal infection and disease, but its efficacy has not been confirmed by randomised controlled trials. or brain calcification (Figure 2) – are rare. The most common sign – Toxoplasma chorioretinitis (Figure 3) – is often missed Figure 1. Life cycle of T. gondii. The culprit – Toxoplasma gondii Sexual reproduction of T. gondii (Figure 1) occurs in the intestines of felines. Infected cats excrete oocysts in faeces which are infective, after several days, if ingested by warm-blooded animals including food-producing livestock and humans. Toxoplasmas spread throughout the body until halted by the host immune response. A few organisms remain dormant but viable, in tissue cysts in muscle, eyes or brain, where they can reactivate if local or systemic immunity is compromised. Epidemiology and risk factors Faecal oocysts mature rapidly in warm, moist conditions; the geographic prevalence of toxoplasmosis is, roughly, inversely proportional to distance from the equator. Humans are infected by eating undercooked meat or by coming into contact with soil contaminated by cat faeces (e.g. on hands or unwashed vegetables) 1. A case control study showed that consumption of undercooked or cured meat products (30-63% of cases), contact with soil (6-17%) and travel outside Europe and North America were the most common risk factors; contact with cats was not 2. 188 MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope at birth but can progress and first present as sight-threatening reactivation during childhood or early adult life. Progressive encephalitis can cause developmental and intellectual delay. Vertical transmission The risk of fetal infection increases from <15% when maternal infection occurs in the first trimester, to 44% in the second and 72% in the third trimester of pregnancy 3, 4. Fetal infection in the first trimester causes symptomatic disease in about 75% of cases, compared with about 15% in the second and none in the third 5, 6. Antenatal screening and diagnosis Routine prenatal screening has been practised routinely in some European countries for many years, but is not recommended in Australia – maternal infection is uncommon and fetal disease rare, the sensitivity and specificity of screening tests are poor and the efficacy of treatment is doubtful. Toxoplasma IgG can be measured by a variety of methods (some of which are historical). Enzyme-linked immunoassays (EIA) are now most commonly used. Seroconversion is the best serological Figure 2. Severe fetal toxoplasmosis. Routine fetal ultrasound examination at about 16 weeks’ gestation showed gross hydrocephalus and ascites and pregnancy was terminated. Toxoplasmosis was confirmed by histological examination of fetal tissues. evidence of recent infection, whereas toxoplasma IgM EIA has poor specificity 7. If IgG and IgM are positive and unchanged when repeated with different kits or on another specimen, further tests are needed to improve specificity, for example: • A quantitative antibody test – e.g. differential agglutination may show a rising titre in paired sera, as toxoplasma IgG titre continues to rise for about 3 months after acute infection. • A double sandwich IgM EIA and IgM immunosorbent agglutination assay (ISAGA) are more specific than commercial IgM EIAs – levels rise and fall rapidly after infection, albeit at variable rates. • IgG avidity is now the standard ‘confirmatory’ test. Following acute infection, the affinity of IgG for specific antigen increases progressively, making disruption of serum antigen/ antibody complexes, e.g. by treatment with 8M urea, increasingly difficult. The avidity index is the ratio of IgG levels (measured by EIA optical density values) in aliquots of treated and untreated serum, tested in parallel. In general, high avidity indicates past and low avidity recent infection. IgG avidity tests are not standardised. A recent review of 11 published studies, involving six in-house and eight commercial IgG avidity tests, showed considerable variation in definitions of low avidity index (from <15% to <50%) and high avidity index (from >20% to >58%) and the maturation period, which defines recent infection (from 3-6 months). Generally, delayed IgG maturation was found in fewer than 5% of subjects but two methods showed poor sensitivity. Occasionally, low avidity persisted for years. In one study, the same method demonstrated Figure 3. T. chorioretinitis. M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 189 Under the Microscope diagnosis or exclusion of recent toxoplasmosis. amniocentesis and treatment, on the accuracy of PCR for diagnosis of congenital toxoplasmosis. The positive predictive values (PPVs) increased, from 0.75 to 0.94 and the NPVs fell, from 0.98 to 0.56 between the first and third trimesters. There was considerable variation in specificity centres 10. If recent toxoplasmosis is likely or cannot be excluded during Treatment delayed maturation in 9.5% of pregnant women compared with 0.9% of non-pregnant subjects. High avidity indices within the maturation period were reported with five methods 8. Despite these limitations, properly validated IgG avidity tests can assist in pregnancy, intrauterine diagnosis is recommended, especially in the first half of pregnancy, because of the high risk of fetal damage. Amniotic fluid PCR, at 18 weeks’ gestation or later, is highly specific and much more sensitive (97%) than mouse inoculation (64%), fetal blood IgM or non-specific inflammatory markers (30-40%) 9. A study in nine European centres examined the effects of gestational age at maternal seroconversion, timing of Electronic submission of manuscripts to the journal Microbiology Australia now requires all submissions to be made online Steps to submission and publication • Go to the publisher’s website: www.cambridgemedia. com.au T. gondii is susceptible to several types of antimicrobial. Workers in some European countries, where routine antenatal screening has been compulsory for years, recommend treatment with spiramycin (a macrolide, which can be used safely in early pregnancy), as soon as possible after the diagnosis. Termination is often recommended for fetal infection in the first trimester because of the high risk of severe disease. Later in pregnancy, spiramycin may be continued or replaced by combined sulphadiazine and pyrimethamine (with folinic acid, to reduce side-effects) 7. There have been no randomised controlled trials of treatment. Despite extensive experience and circumstantial evidence of efficacy 5, 6, a recent systematic review of published cohort studies 4 and a large case review 11, only weak evidence that treatment reduced placental transmission was found and none that it reduced clinical manifestations; there were, however, significant biases in selection of treated cases and controls. It is therefore likely that benefits are greatest in or limited to cases in which treatment is started within 3-4 weeks of maternal infection 4, 11. • Click on Manuscript System. References • Login. 1. • Create an account if first time using the system. This will be retained for future enquiries and submissions. Montoya, J. G. and Leisenfeld, O. (2004) Toxoplasmosis. Lancet, 363, 19651976. 2. • Enter your personal details: all fields must be completed. Cook, A.J. et al. (2000) Sources of toxoplasma infection in pregnant women: European multicentre case-control study. European Research Network on Congenital Toxoplasmosis. BMJ 321, 142-127. 3. Dunn, D. et al (1999) Mother-to-child transmission of toxoplasmosis: risk estimates for clinical counseling. Lancet 353, 1829-1833. 4. Submitting an article The SYROCOT (Systematic Review on Congenital Toxoplasmosis) study group. (2007) Effectiveness of prenatal treatment for congenital toxoplasmosis: a meta-analysis of individual patients’ data. Lancet 369, 115-122. 5. • Step 1 – Type the title, type of paper and abstract. Select publication – Microbiology Australia. Hohlfeld, P. et al. (1989) Fetal toxoplasmosis: outcome of pregnancy and infant follow-up after in utero treatment. J. Pediatr. 115, 765-769. 6. Couvreur, J. et al. (1993). In utero treatment of toxoplasmic fetopathy with the combination pyrimethamine-sulfadiazine. Fetal Diagn. Ther. 8, 45-50. 7. Petersen E. (2007). Toxoplasmosis. Semin. Fetal Neonat. Med. 12, 214-223. 8. Lefevre-Pettazzoni, M. (2006) Delayed maturation of immunoglobulin G avidity: implication for the diagnosis of toxoplasmosis in pregnant women. Eur. J. Clin. Microbiol. Infect. Dis. 25, 687-693. 9. Hohlfeld, P. et al. (1994) Prenatal diagnosis of congenital toxoplasmosis with a polymerase-chain-reaction test on amniotic fluid. N. Engl. J. Med. 331, 695699. • Confirm your details. • Step 2 – Confirm author. Add co-author details (all fields) if applicable. • Step 3 – Upload files. Only Word documents are accepted. Please ensure your document contains the required information and is formatted according to the author guidelines. • Step 4 – Add any comments for the editor. • Step 5 – Review your information then click submit. Once submitted, the manuscript is reviewed by the editor and, if acceptable, sent for peer review. Peer review Peer reviewers will be asked to review the manuscripts through the electronic process. 190 10. Thalib, L. et al (2005) Prediction of congenital toxoplasmosis by polymerase chain reaction analysis of amniotic fluid. BJOG 112, 567-574. 11. Gilbert, R. et al (2001) Effect of prenatal treatment on mother to child transmission of Toxoplasma gondii: retrospective cohort study of 554 motherchild pairs in Lyon, France. Int. J. Epidemiol. 30, 1303-1308. Professor Lyn Gilbert is an infectious disease physician and clinical microbiologist, director of the Centre for Infectious Diseases and Microbiology, ICPMR, Westmead, NSW and clinical professor in medicine at the University of Sydney. She has longstanding clinical and research interests in infections in pregnancy and the newborn, in vaccine preventable diseases and in bacterial infections of public health importance. MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 TriState 2008 Alice Springs 12 – 13 September 2008 Post-Event Report www.tristate2008.org The ASM TriState meeting was initiated by members of the SA, WA and NT branches several years ago to provide for a regional meeting specifically to focus on local issues and themes; to be held every three years in the Northern Territory. Once again supported by the ASM, this year’s TriState meeting was held in Alice Springs from 12 – 13 September at the Crowne Plaza Hotel. Professor Henri Verbrugh, University Medical Centre – The Netherlands at TriState 2008. It has always been the intention of TriState for the meeting to be held in a relaxed and informal atmosphere conducive to discussion of local issues and to provide an environment for networking – this year was no exception with the program providing several such opportunities. With an all inclusive registration fee making things easier for delegates, the meeting kicked-off on Friday with a networking luncheon providing everyone with their first opportunity to catch up with old acquaintances and a chance to make new ones. The afternoon sessions then focussed on the big (parasitology) and small (virology) ends of microbiology. Dr Andrew Butcher gave an excellent update on the diagnosis of Entamoeba histolytica which was followed by a number of quite stunning case presentations by Dr Harsha Sheorey. Dr David Smith spoke with his usual expertise on the topics of Arboviruses of the Top End and issues related to the application & point of care testing in virological diagnoses, and Dr Geoff Higgins presented a first class review of viral gastroenteritis. The afternoon sessions were capped with a Welcome Mixer of fine NT tastes which then extended into the evening for some enjoying a warm night by the pool! Saturday morning commenced with a selection of some of the best talks from the International Symposium on Staphylococcal Infections (ISSI) which was held in Cairns just a few days prior. Overseas special guest speaker, Professor Henri Verbrugh, spoke on aspects of Staph. aureus infection, Geoff Coombs on the molecular diagnosis of MRSA and Dr Graeme Nimmo on community MRSA. Later that morning, Dr Michael Watson and Associate Professor Amanda Leach presented pneumococcal surveillance data and non-vaccine serotype replacement problems respectively, with the session rounded out by Dr Duncan McLellan speaking on clinical aspects and genotyping of group A streptococci. After lunch, Professor Tom Riley presented an excellent overview on the epidemiology of Clostridium difficile and Paul Southwell spoke of his experience with the establishment of the new PC3 facility at Royal Darwin. Sincere thanks is extended to both Tom and Paul for assisting with some last minute program changes. The final session was an update on sexually transmitted infections with Professor Sue Garland presenting very recent data on the WHINURS project in which Alice Springs played a key role. Dr David Whiley gave an excellent review on the molecular diagnosis of STIs with the meeting completed by Professor Verbrugh discussing pregnancy outcomes in women infected with Chlamydia trachomatis. In my closing remarks I commented on the quality and diversity of the speakers and the first-class talks they had just presented. I reiterate my comments and sincere thanks to the speakers for their time and invaluable contribution and also to our corporate sponsors BD, Roche and bioMerieux for their continued support. Saturday night’s “Conference Dinner” was a relaxed outdoor Territorian Feast held on the lawns poolside featuring a special guest presentation by well-known local astronomer with the aid of his telescope. Fantastic contributions by the speakers, excellent delegate networking and generosity of the sponsors combined with the pleasant and relaxed atmosphere made for an excellent meeting that I think was enjoyed by all. We now look forward to the next TriState meeting in three years with some discussion as to alternating between Alice Springs and Darwin. I encourage you to attend as this truly is a unique and rewarding networking & learning experience! Rod Bowman Chair, TriState 2008 Organising Committee ASM 2009 Perth 6 – 10 July 2009 & Perth Convention Centre WA www.asm2009.org Invitation You are invited to attend the Perth 2009 Annual Scientific Meeting & Exhibition to help ASM celebrate its 50th Golden Jubilee Year! The conference will provide many opportunities for you to stay up to date with the latest technology, industry practices and global issues. NSAC and the Scientific Program Committee have been working hard to produce a program that is relevant to all Divisions across the Society and also thought provoking. A S M ’ s 5 0 t h G o l d e n J u b i l e e Ye a r ! over the coming months – stay tuned for the Early Bird Registration Society for Microbiology will co-sponsor a special guest speaker for and abstract submission announcements so that you don’t miss the meeting, Professor Rita Colwell, a world-renowned authority these important deadlines. on microbiology and climate change and past President of the American Society for Microbiology. We look forward to seeing you in Perth next year! Professor Bonnie Bassler – Rubbo Orator Rod Bowman | Chair, ASM 2009 Perth Local Organising Professor of Molecular Biology, Princeton University, Princeton, Committee New Jersey USA Scientific Program The Rubbo Oration is the key plenary session of the ASM Scientific Meeting honouring the contribution of Dr Sydney Rubbo to the society and microbiology more generally. The evening plenary is followed by supper and is supported by the University of Melbourne, Rubbo Trust. July 2009 will see Perth host a world class gathering of eminent microbiologists to discuss various issues of current relevance to the microbiological community. The range of topics to be discussed and the high quality of the invited speakers ensures that the meeting will likely attract many senior hospital and laboratory scientists and medical staff as well as researchers and teachers from all aspects of the microbiology community. We anticipate 800+ delegates to attend the conference and the exhibition will provide a perfect opportunity to see the latest industry and technical advancements. The Social Program Committee are also working hard to bring you enjoyable and relaxing functions to stimulate and continue your networking. Especially exciting elements to the Social Program are being planned to celebrate ASM’s achievement of 50 years and we would love for you to come and celebrate with us! The theme of “Reflection and Direction” acknowledging both the Society’s 50th birthday, and future directions in the field of microbiology. The American Society of Microbiology has agreed to co-sponsor a special guest speaker as it formally acknowledges and celebrates our 50th anniversary with us. The new Perth Convention Centre is a purpose-built world class facility nestled between the beautiful Swan River, the city centre and King’s Park. The centre and its immediate surrounds offer some excellent locations and environments for trade focussed opportunities. Perth’s location puts it us easy reach of our Pacific Rim colleagues and we will be encouraging their attendance ensuring an even wider networking platform. Once again, discounted accommodation rates have been negotiated with a variety of hotels and apartments within walking distance to the convention centre. Visit the website for full conference information as this is developed Introduction The conference will bring you some of the respected Microbiologists in the world as keynote speakers. ASM 2009 Perth will feature presenters from a range of sub-disciplines in microbiology that will provide a unique opportunity to experience several plenary sessions of world class standard. Keynote Speakers Professor Rita Colwell, USA Chairman, Canon US Life Sciences, Distinguished Professor, University of Maryland, College Park Distinguished Professor, Johns Hopkins University, Bloomberg School of Public Health To acknowledge and celebrate ASM’s Golden Jubilee, the American The Perth 2009 Rubbo Oration will be delivered by Dr Bonnie Bassler, Professor of Molecular Biology at Princeton University. Professor Bassler is a world authority on mechanisms of quorum sensing in bacteria (how bacteria “talk” to each other) and was awarded a MacArthur Fellowship in 2002 and elected to the National Academy of Sciences in 2006 in recognition of her work. Further, the delivery of her presentations is made in such a way that captures the complete imagination and involvement of her audience. This will be a function not to be missed. Dr Rino Rappuoli – Bazeley Orator (sponsored by CSL) Vice President & Chief Scientific Officer, Vaccines Research, Chiron Vaccines, Sienna, Italy Dr Rappuoli is credited with co-founding the field of “cellular microbiology”, a discipline which combines cell biology and microbiology and has pioneered the genomic approach to vaccine development called “reverse vaccinology”. Dr Rappuoli has been involved in pandemic influenza preparedness activities for many years, including the production and clinical testing of potential pandemic vaccines. Dr Thomas Ksiazek – Snowdon Lecturer (sponsored by AAHL, CSIRO) Chief, Special Pathogens Branch, Division of Viral and Rickettsial Diseases, National Centre for Infectious Disease, Centers for Disease Control, Atlanta, Georgia Dr Ksiazek has worked as a veterinary microbiologist at stations around the world for the US Navy, US Air Force and then the US Army at the Defense Assessment Division at Fort Detrick, Maryland. His military career saw numerous academic awards and Army, Navy and Air Force Commendation Medals. He took up his current position as Chief Special Pathogens Branch, Centers for Disease Control, Atlanta Georgia in 1991 after 20 years of active Plenary Presentation: Climate, oceans, infectious disease and human health - A new perspective Symposia Topics: Metagenomics and environment Validating probiotic functionality in clinical and animal trials Out of left field: the microbiology of the Australian rhizosphere Current topics in food microbiology Biological threat assessment Microbial Informatics Prevention of biofilms on medical devices Culture media Water microbiology Vibrio Division 4 – Microbial Genetics, Physiology & Pathogenesis David Stephens - Professor of Microbiology and Immunology, Emory University School of Medicine Plenary Presentation: Vaccine design focussing on selected innate immunity pathways and adjuvants duty service. Dr Ksiazek has authored and co-authored over 200 publications in his career. Associate Professor Elizabeth Harry – ASM 2009 Fenner Lecturer University of Technology Sydney Associate Professor Harry has been awarded the prestigious ASM Frank Fenner Award for 2009 and has a long standing interest in the subject of bacterial cell division. Opening Ceremony Professors Barry Marshall and John Mackenzie will present joint plenary sessions for the Opening Ceremony. Professor Barry Marshall Nobel Laureate (Physiology and Medicine, 2005) Professor of Clinical Microbiology, University of Western Australia Co-Director, Marshall Centre for Infectious Disease Research and Training Professor Barry Marshall is an Australian physician and is known world-wide for his role in the demonstration of Heliocobacter pylori being the primary cause of stomach ulcers. He has received numerous other prestigious awards for his ground -breaking research and was awarded a Companion of the Order of Australia in 2007. Division 2 - Virology Susan Gottesman - Chief of Biochemical Genetics, Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health Ian Lipkin - Professor of Epidemiology, Columbia University Mailman School of Public Health Plenary Presentation: Small RNAs and the Bacterial Stress Response Plenary Presentation: Pathogen Discovery Symposia Topics: Mechanisms of gene regulation in bacteria Innate immune response to microbial products How microbial genomics informs novel approaches to vaccine design Parasite/Host interactions Nuts and bolts: how protein structure relates to function in the microbial world Bacterial/Host interactions Microbial evolution Paradigms in microbial pathogenesis Building a home- the cell wall Moving home- biofilms and motility Mycobacteria Diane Griffin - Professor and Chair in Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health Plenary Presentation: Alphavirus Determinants of outcome encephalomyelitis - Symposia Topics: Gastroenteritis Parvoviruses Emerging threats Virus-Host Interactions Viral encephalitis Enteroviruses Animal viruses Respiratory viruses Molecular epidemiology / surveillance HIV To Be Announced The following dates and details will be announced over the coming weeks: Division 3 – General, Applied & Environmental Microbiology • R egistration – Early Bird rates & deadline, discounted ASM member and student rates Professor John Mackenzie Honorary Professor, University of Queensland Curtis Suttle - Professor of Earth & Ocean Sciences, University of British Columbia • A bstract Submission – deadline date, submission categories and how to submit Professor Mackenzie is a past President of the ASM and has held many other positions in international microbiology societies. Recently “retired”, Prof Mackenzie maintains a keen involvement in many projects and is a world authority on arboviral infections. Plenary Presentation: The virosphere - The largest reservoir of unexplored diversity on the planet • Social Program – function details & ticket costs • Local Perth Accommodation – room descriptions & rate, how to book Invited International Speakers International speakers invited by the four Divisions of NSAC are listed below followed by the proposed range of symposia to be presented by each division. Division 1 – Medical & Veterinary Microbiology Ellen-Jo Baron - Professor of Pathology, Stanford University School of Medicine Plenary Presentation: Diagnostic Microbiology - The Future is NOW Lance Peterson - Professor and Director, Clinical Microbiology and Infectious Diseases Research Division, Evanston Northwestern Healthcare Plenary Presentation: The emerging role of the diagnostic laboratory in infection control Symposia Topics: Anaerobes Clostridium difficile Meningococcal disease Laboratory diagnosis of respiratory tract infections MRSA Pneumococcal disease Mycology Laboratory diagnosis of genital tract infections Tropical medicine Robert Hancock - Professor of Microbiology and Immunology, University of British Columbia Plenary Presentation: Antibiotic resistance and how to overcome it Details will published to the conference website – www.asm2009.org Rita Colwell - Professor of Microbiology and Biotechnology, University of Maryland Conference Organisers – Australian Society for Microbiology Under the Microscope Diagnosis and treatment of herpes simplex virus (HSV) infection in the newborn Cheryl A Jones Discipline of Paediatrics and Child Health, University of Sydney, NSW Centre for Perinatal Infection Research, The Children’s Hospital at Westmead, Westmead NSW 2145 Tel (02) 9845 3382 Fax (02) 9845 3389 Email [email protected] Neonatal herpes simplex virus (HSV) disease is a rare but sometimes highly lethal infection. The reported incidence in Australia is approximately four cases per 100,000 live births 1. HSV type 2 (HSV-2) is the predominant serotype that causes infection in the newborn in the United States 2, whereas in Australia 1 neonatal infection is usually caused by HSV type 1 (HSV-1), most likely due to greater prevalence of oral and genital HSV-1 disease in this country 3. Diagnosis of neonatal infection requires a high index of clinical suspicion as signs are non-specific, and is usually confirmed by isolation of HSV from skin vesicle or detection of HSV DNA in the cerebrospinal fluid, blood or surface swab. Treatment requires intravenous aciclovir for 14-21 days depending on the form of disease. Presentation and route of infection a term infant typically on Day 3-5 of life. SEM disease carries a very low to no risk of mortality, but carries a high risk of spread to the central nervous system if untreated with antiviral therapy and a risk of neurological impairment in late infancy. Neonatal HSV encephalitis has a high mortality rate which is significantly reduced by prompt initiation of systemic antiviral therapy, but survivors have a high risk of neurological sequelae. Multi-organ HSV disease in the newborn is also often lethal, even with antiviral therapy 4. The strongest risk for vertical transmission of HSV is primary genital infection during late pregnancy 5, 6. Some studies suggest that genital HSV-1 disease is more readily transmissible to the neonate than HSV-2, but this requires confirmation 6. If virus is in the genital tract at delivery, invasive obstetric procedures such as instrument deliveries and fetal scalp electrodes increase the risk of transmission to the newborn 6. The diagnosis of neonatal herpes Clinical features The presenting features of neonatal HSV infection are nonspecific, which may result in missed or delayed diagnosis. Typical skin vesicles may be absent in up to 30% of infected infants, particularly in those with encephalitis or multi-organ disease. Fever is only present in just under half of the infected infants. Systemic disease may manifest as lethargy, seizures, jaundice or respiratory distress. Laboratory diagnosis Viral culture, PCR and direct immunofluorescence The majority (85%) of infants become infected with HSV at the time of delivery by passage through an infected birth canal. A further 10% acquire the infection from contact with infectious lesions, usually on the hands or lips of a caregiver after delivery. The remaining 5% of HSV infected infants have a congenital infection, i.e. become infected in utero by transplacental spread of virus. Specimens that should be collected from an infant with suspected neonatal HSV disease include cerebrospinal fluid (CSF), surface swabs from skin vesicles, conjunctiva, nasopharynx and rectum, and blood for full blood count, liver function tests, and coagulation studies (if systemic disease is suspected). Central nervous system imaging (computer tomographic scan or magnetic resonance imaging) and chest radiographs may also be indicated. Congenital HSV infection presents with distinct manifestations at birth – usually eye abnormalities, skin scarring, microcephaly and sometimes central nervous system calcification on imaging. Perinatal HSV infection, acquired at the time of delivery or in the postnatal period, may present in three ways. Disease may be confined to the skin, eye, or mouth (SEM disease), to the central nervous system alone, or the infection can present with multiorgan ‘septic shock’ with or without encephalitis. Surface swabs may be analysed by viral culture and/or polymerase chain reaction (PCR) for HSV DNA. HSV induces a typical cytopathic effect in 2-4 days on cell monolayers which can be subsequently serotyped. Rapid confirmation of HSV infection can be obtained by direct immunofluorescence of surface swabs that have been plated on to a glass slide. The sensitivity of this technique is only 40-50%, so a negative result does not exclude the diagnosis 2. Neonatal HSV pneumonitis is a highly lethal variant of disseminated infection which presents as respiratory distress in CSF from neonates should be analysed for cell count and biochemistry, and should always be set up for viral culture in 194 MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope addition to PCR; positive CSF cultures have been reported in up to 20% of infants with neonatal HSV disease in contrast to the low yield obtained from adults with HSV encephalitis 7. The sensitivity of HSV PCR in the CSF is reportedly lower for neonatal herpes (71–100%) than for adults with HSV encephalitis (>95%) 8. The rate of detection of HSV DNA in the CSF decreases in most cases after infants have been on antiviral therapy for over a week 9. A repeat CSF specimen should be performed at the end of therapy to confirm the absence of HSV DNA, which can be associated with early relapse and late neurological sequelae. Some groups have used quantitative HSV PCR on CSF samples to provide prognostic information in adults with HSV encephalitis, with an HSV viral load >100 copies/ml being associated with poor neurological outcome 10. This is not in routine clinical use, and similar studies have yet to be conducted in neonates. PCR assays for HSV DNA have also been performed on blood from infants with neonatal HSV infection. HSV DNA was detected in PBMC or plasma from 60-70% of infected infants in one study 11. Serology Type specific IgM or IgG serology for HSV has a limited role in the acute diagnosis of HSV infection in the neonate. Only 40% of infants develop HSV-type specific IgM responses in neonates and their response is usually too slow to guide therapy 2. Serology may play a role in counselling parents postnatally as to the origin of neonatal HSV disease as most women who deliver an infant with neonatal HSV disease are unaware of their own genital HSV disease until the infant is diagnosed 6. Serology may also assist in the diagnosis of nosocomial infections. Routine antenatal type specific serology is controversial and probably not indicated in countries with low HSV-2 seroprevalence like Australia 12-15. However, it may play a role in isolated cases for counselling serodiscordant couples about risks of vertical HSV transmission in future pregnancies. The treatment of the neonatal HSV disease Current recommendations for antiviral therapy for neonatal HSV disease are listed in Table 1. Clinical trials have confirmed that vidarabine and aciclovir are equally efficacious in reducing mortality from neonatal HSV disease 16; however, intravenous aciclovir has become the standard therapy because it has less toxicity and is easier to administer. The duration of therapy depends on the type of neonatal HSV disease. Infants with SEM disease should be treated for 14 days, whereas infants with disseminated infection, encephalitis or where a lumbar puncture has not been performed, should be treated for 21 days. Katoomba Blue Mountains, NSW 7 – 9 May 2009 www.virusesinmay.com Annual intensive clinical virology update for clinicians, scientists and trainees in this discipline Australia’s only meeting focused specifically on the clinical, diagnostic and management aspects of viral infections. Program themes include: • Principles of clinical virology • Congenital infection, paediatric infection and vaccination • Blood borne viruses and hepatitis Invited speakers include: • Associate Professor Cheryl Jones, Children’s Hospital Westmead • Emeritus Professor Yvonne Cossart, University of Sydney • Professor Richard Strugnell, Microbiology University of Melbourne • Professor William Rawlinson, Virology Prince of Wales Hospital • Dr Carl Kirkwood, Royal Children’s Hospital Melbourne • Philip Cunningham , NSW State Reference Library for HIV/AIDS • Professor David Isaacs, Immunology & Infectious Diseases, Children’s • Dr Peter Robertson, Microbiology Prince of Wales Hospital • Associate Professor Alison Kesson, Children’s Hospital Westmead • Dr David Smith, PathWest Laboratory Medicine • Dr Nham Tram, Centenary Institute of Cancer • Dr Mike Catton, VIRDL • Associate Professor Stephen Riordan, Gastrointestinal & Liver Unit • Dr Jeffrey Post, Infectious Diseases Physician Prince of Wales Hospital Prince of Wales Hospital • plus other speakers still to be confirmed • Hospital Westmead • Professor Robert Booy, National Centre for Immunisation Research & Surveillance Dr Monica Lahra, University of Sydney See website for preliminary scientific program & invited speakers. Discount accommodation rates at conference venue available for delegates Discount registration available to ASM members & full-time students – Early Bird registration opportunity Convenors: Professor William Rawlinson – Director, Virology Division Microbiology Dept, Prince of Wales Hospital NSW Dr Monica Lahra – Dept Immunology & Infectious Diseases, University of Sydney Conference Organisers – Australian Society for Microbiology www.virusesinmay.com M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 195 Under the Microscope The dose and duration of IV aciclovir for neonatal HSV disease has been increased over the last decade to 60mg/kg/day, administered in three equal doses in order to reduce disease progression and mortality from disseminated infection or encephalitis. These changes have not been formally studied in randomised controlled trials due to the low frequency of the condition, but were reported in an open label study to result in increased survival for infants with disseminated HSV disease and to reduce long-term neurological sequelae compared to historical controls 17. Infants on high dose aciclovir should have their neutrophil counts and hydration monitored throughout therapy, and dose should be adjusted for renal function. Other antiviral agents are not generally used to treat neonatal HSV disease. Foscarnet has been used in neonates with severe viral disease, or on the rare occasion where aciclovir resistance is suspected. Oral aciclovir should not be used for the acute treatment of neonatal HSV disease due to low bioavailability and the failure to achieve adequate CNS concentrations that will inhibit viral replication. There are no current data available about the use of oral antiviral preparations with better bioavailability for the treatment of this condition. Suppressive antiviral therapy to prevent long-term neurological sequelae from neonatal HSV disease has been trialled 18. However, this practice is associated with a high rate of drug induced neutropenia, and isolated reports of late CNS recurrences on therapy and isolation of aciclovir-resistant mutants, so is not routinely recommended 18-20. The use of antiviral therapy in pregnant women or their partners to prevent vertical transmission of HSV disease is reviewed elsewhere 21, 22. Conclusion Neonatal HSV disease remains an uncommon but important cause of infant death and childhood neurological morbidity. As clinical signs at presentation are non-specific, and a history of maternal genital disease often absent, diagnosis requires a high index of clinical suspicion and prompt laboratory investigation. Table 1. Aciclovir therapy for neonatal HSV disease. References 1. Jones, C.A. et al. (2008) Neonatal HSV disease in Australia. Report of Australian Paediatric Surveillance Unit, 2005-2006, p.24. 2. Whitley, R. (2007) Herpes simplex viruses. In: Fields Virology (5th ed). (Knipe, D.M., and Howle, P.M., eds). p.2502-2576, Philadelphia (PA): Wolster KluwerLippincott Williams & Wilkins. 3. Malkin, J.E. (2004) Epidemiology of genital herpes simplex virus infection in developed countries. Herpes 11, Suppl 1, 2A-23A. 4. Whitley, R. et al. (1991) Predictors of morbidity and mortality in neonates with herpes simplex virus infections. The National Institute of Allergy and Infectious Diseases Collaborative Antiviral Study Group. N. Engl. J. Med. 324, 450-454. 5. Brown, Z.A. et al. (2003) Effect of serologic status and Cesarean delivery on transmission rates of herpes simplex virus from mother to infant. JAMA 289, 203-209. 6. Brown, Z.A. et al. (1991) Neonatal herpes simplex virus infection in relation to asymptomatic maternal infection at the time of labor. N. Engl. J. Med. 324, 1247-1252. 7. Tyler, K.L. Herpes simplex virus infections of the central nervous system: encephalitis and meningitis, including Mollaret’s. Herpes 2004; 11 Suppl 2, 57A-64A. 8. Kimura, H et al. (1991) Detection of viral DNA in neonatal herpes simplex virus infections: frequent and prolonged presence in serum and cerebrospinal fluid. J. Infect. Dis. 164, 289-293. 9. Kimberlin, D. (2004) Herpes simplex virus, meningitis and encephalitis in neonates. Herpes 11 Suppl 2, 65A-76A. 10. Domingues, R.B. et al. (1998) Application of competitive PCR to cerebrospinal fluid samples from patients with herpes simplex encephalitis. J. Clin. Microbiol. 36, 2229-2234. 11. Diamond, C. et al. (1999) Viremia in neonatal herpes simplex virus infections. Pediatr. Infect. Dis. J. 18, 487-489. 12. Wilkinson, D. et al. (2000) HSV-2 specific serology should not be offered routinely to antenatal patients. Rev. Med. Virol. 10, 145-153. 13. Brown, Z.A. (2000) HSV-2 specific serology should be offered routinely to antenatal patients. Rev. Med. Virol. 10, 141-144. 14. Copas, A.J. et al. (2002) An evidence based approach to testing for antibody to herpes simplex virus type 2. Sex Transm. Infect. 78, 430-434. 15. Lafferty, W.E. (2002) The changing epidemiology of HSV-1 and HSV-2 and implications for serological testing. Herpes 9, 51-55. 16. Whitley R. et al. (1991) A controlled trial comparing vidarabine with aciclovir in neonatal herpes simplex virus infection. Infectious Diseases Collaborative Antiviral Study Group. N. Engl. J. Med. 324, 444-449. 17. Kimberlin, D.W. et al. (2001) Safety and efficacy of high-dose intravenous aciclovir in the management of neonatal herpes simplex virus infections. Pediatrics 108, 230-238. 18. Kimberlin, D.W. et al. (1996) Administration of oral aciclovir suppressive therapy after neonatal herpes simplex virus disease limited to the skin, eyes and mouth: results of a phase I/II trial. Pediatr. Infect. Dis. J. 15, 247-254. 19. Levin, M.J. et al. (2001) Development of aciclovir-resistant herpes simplex virus early during the treatment of herpes neonatorum. Pediatr. Infect. Dis. J. 20, 1094-1097. Type of neonatal HSV disease Duration of therapy Skin, eye, mouth 14 days Central nervous system 21 days* Disseminated infection 21 days* 21. Hollier, L.M. and Wendel, G.D. (2008) Third trimester antiviral prophylaxis for preventing maternal genital herpes simplex virus (HSV) recurrences and neonatal infection. Cochrane Database Syst. Rev. Issue 1. Art. No.: CD004946. DOI: 10.1002/14651858.CD004946.pub2. LP not performed at diagnosis 21 days* 22. Jones, C.A. Vertical transmission of genital herpes: prevention and treatment options. Pediatr. Drug. (in press). Dose: 60mg/kg/day divided into three equal doses and given every 8 hours intravenously as 1 hour infusion * Duration should be extended if HSV DNA PCR remains positive at the end of therapy. 196 20. Fonseca-Aten, M. et al. (2005) Herpes simplex virus encephalitis during suppressive therapy with aciclovir in a premature infant. Pediatrics 115, 804849. Cheryl Jones in a paediatric infectious diseases specialist who runs an outpatient service dedicated to the diagnosis, management and treatment of congenital and perinatal infections, and heads the Centre for Perinatal Infection Research to investigate the epidemiology and pathogenesis of these infections. MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope Respiratory infections in the newborn Michael D Nissen Theo Sloots Queensland Paediatric Infectious Diseases Laboratory Department of Infectious Diseases Sir Albert Sakzewski Virus Research Centre Royal Children’s Hospital Brisbane QLD 4029 Tel (07) 3636 8654 Email [email protected] Queensland Paediatric Infectious Diseases Laboratory Department of Infectious Diseases Sir Albert Sakzewski Virus Research Centre Royal Children’s Hospital Brisbane QLD 4029 Tel (07) 3636 8833 Email [email protected] It is well recognised that acute respiratory tract infection (ARTI) occurs commonly in children younger than 5 years of age, with pneumonia being the most serious complication 1. The greatest risk of death from pneumonia in childhood is in the neonatal period 2; it is estimated that pneumonia contributes to between 0.75-1.2 million neonatal deaths annually, accounting for approximately 10% of global child mortality 3. Of all neonatal deaths due to pneumonia, 96% occur in the developing world 4. ARTIs in neonates can be classified as congenital or neonatal in origin, and are defined by the timeframe in which the infection or pathogen has been acquired. Congenital pneumonias are usually part of a transplacental infection, while neonatal pneumonias can evolve from intrauterine or postnatal acquisition. Neonatal pneumonia is classified as early or late onset 2. Early onset neonatal pneumonia, in general, is defined as a clinical presentation in the first 48 hours up to 1 week of life, while late onset neonatal pneumonia occurs in the following 3 weeks. Congenital and neonatal pneumonias are often a difficult disease to identify and treat. Clinical manifestations are generally nonspecific, sharing respiratory and a range of non-inflammatory processes. Laboratory findings also have limited value, with attempts to identify specific microbes often unsuccessful due to difficulty in their recovery from intrapulmonary sites without contamination. In addition, many organisms are primarily uncultivable or uncultivable due to antimicrobial therapy. Bacterial respiratory pathogens The pathogens commonly associated with neonatal and congenital pneumonia include numerous bacteria, fungi and viruses (Table 1). Bacterial pneumonia derived from infected amniotic fluid or colonisation of the birth canal is linked with maternal chorioamnionitis and fetal asphyxia. It is assumed that asphyxia leads to fetal gasping and aspiration of infected amniotic fluid. This hypothesis is based on the histological finding of M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 amniotic fluid and/or maternal white blood cells in the affected neonatal lungs 2. The bacterial aetiology of neonatal pneumonia is also influenced by nosocomial infection in neonatal intensive care units. High rates of Streptococcus pneumoniae have been reported in late onset neonatal pneumonia in some areas of the world 5. Atypical bacterial pathogens, for example Chlamydia trachomatis, are well recognised as agents of late onset pneumonia causing infection at 1-3 months of age. The ability to now perform C. trachomatis polymerase chain reaction (PCR) testing on nasopharyngeal or endotracheal aspirates from infants with neonatal pneumonia has increased the rate of detection of this pathogen. It is assumed that C. trachomatis contributes significantly to neonatal pneumonia in countries where untreated sexually transmitted diseases in women are common. In addition, Bordetella pertussis may present as an early onset or late onset pneumonia, and is most commonly associated with close contact with an infected parent, siblings, relative or healthcare worker. Other atypical bacteria that have been associated with pneumonia or pneumonitis in the neonate are Ureaplasma urealyticum and Ureaplasma parvum, Treponema pallidum, Mycobacterium tuberculosis and Listeria monocytogenes 5. A persistent neonatal pneumonia associated with a rapidly progressive presentation of congenital HIV infection has been previously described in two Southern Africa studies 6, 7. Coinfections with M. tuberculosis, syphilis and cytomegalovirus were common and realistically contributed to the clinical presentation. Congenital HIV infection also increases the fatality risk from neonatal respiratory distress syndrome and sepsis associated with S. pneumoniae and Staphylococcus aureus. Viral respiratory pathogens Viral neonatal pneumonias can either be associated with intrauterine, early onset or late onset pneumonias, and may be acquired from the birth canal (e.g. herpes simplex virus – 197 Under the Microscope HSV), infected siblings, parents and/or healthcare workers with or without nosocomial involvement (e.g. respiratory syncytial virus). HSV is usually transmitted during delivery through an infected maternal genital tract and respiratory symptoms are normally associated with multi-organ disease. Transplacental transmission of virus and hospital-acquired spread from one neonate to another by hospital personnel or family may account for 15% of cases. Mothers of neonates with HSV infection tend to have no history or symptoms of genital infection at the time of delivery. The role of respiratory viruses (respiratory syncytial virus, influenza viruses, parainfluenza viruses, adenovirus and human metapneumovirus) in neonatal pneumonia is well described by retrospective reports 8 and is associated with seasonal late onset pneumonia where viral diagnostic techniques are accessible. Nosocomial outbreaks of respiratory viruses in neonatal nurseries and co-infections with respiratory syncytial virus and human metapneumovirus have also been described 9. Diagnosis of neonatal respiratory infections To diagnose neonatal respiratory infection, chest x-rays should be performed in any patient with respiratory abnormalities, and blood should be collected for culture in all cases of neonatal pneumonia. While the yield from blood cultures is low, blood, if possible, should be collected prior to antibiotic therapy to guide second-line treatment in the event of first-line antibiotic failure. Blood cultures collected simultaneously with endotracheal tube aspirates in mechanically ventilated neonates may also assist in determining the significance of endotracheal tube colonisation. Conventional bacteriologic culture is used most widely and is currently most helpful in diagnosing neonatal pneumonia. The culture of fungi, viruses, Ureaplasma urealyticum, and other unusual organisms often requires different microbiologic processing but may be warranted in suggestive clinical settings. A number of factors may interfere with the ability to cultivate a likely pathogen from the sites noted, including (but not limited to): pretreatment with antibiotics that limit in vitro but not in vivo growth; contaminants that overgrow the pathogen; pathogens that do not replicate in currently available culture systems; sampling of an inappropriate site; and patients in whom the process is inflammatory but not infectious, such as with meconium aspiration. Techniques that may help overcome some of these limitations include antigen detection, serologic tests, nucleic acid probes and PCR-based assays. Particularly in the diagnosis of viral respiratory pathogens, molecular methods have significantly enhanced our ability to diagnose these infections. Additionally, these sensitive assays have led to the recognition of new viruses associated with the human respiratory tract, including in neonates, yet the significance of these as agents of disease remains unclear 10. Conclusion In summary, the global impact of neonatal pneumonia is significant, with a complex epidemiology and aetiology compared to the pneumonias in older children. Management and prevention strategies for neonatal pneumonia cross multiple levels of the population and health care provision, and have broader based effects that are sometimes difficult to measure. Table 1. Pathogens associated with congenital and neonatal pneumonia. Bacteria Serratia spp. Fungii Acinetobacter spp. Staphylococcus aureus Candida albicans Enterobacter aerogenes Staphylococcus epidermiditis Pneumocystis jiroveci Enterococcus spp. Streptococcus pneumoniae Atypical microorganisms Escherichia coli Streptococcus viridans group Group A Streptococcus (S. pyogenes) Viruses Group B Streptococcus (S. agalactiae) Herpes simplex virus Listeria monocytogenes Group D & G streptococci Human adenoviruses Mycobacterium tuberculosis Haemophilus influenzae (non-typable) Human cytomegalovirus Treponema pallidum Klebsiella spp. Human immunodeficiency virus Ureaplasma urealyticum Morganella spp. Human metapneumovirus Ureaplasma parvum Neisseria meningitidis Influenza A & B viruses Proteus spp. Parainfluenzae viruses 1, 2 & 3 Pseudomonas aeruginosa Respiratory syncytial virus Bordetella pertussis Chlamydia tracheomatis Salmonella spp. 198 MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope The growing prevalence of antibiotic resistance to common and affordable antibiotics will eventually impact on the morbidity and mortality rates for neonates, especially in the developing world, and emphasises the importance of the continuing development of universal maternal and preventative health programmes. References 1. Arnold, J.C. et al. (2006) Human bocavirus: prevalence and clinical spectrum at a children’s hospital. Clin. Infect. Dis. 43, 283-288. 2. Duke, T. (2005) Neonatal pneumonia in developing countries. Arch. Dis. Child. Fetal. Neonatal. Ed. 90,F211-F219. 3. The Child Health Research Project (1999) Reducing perinatal and neonatal mortality: report of a meeting Baltimore, Maryland. Baltimore, 3, 6-12. 4. Black, R.E. et al. (2003) Where and why are 10 million children dying every year? Lancet 361, 2226-2234. 5. Nissen, M.D. (2007) Congenital and neonatal pneumonia. Paediatr. Respir. Rev. 8, 195-203. 6. Pillay, T. et al. (2001) Severe, rapidly progressive human immunodeficiency virus type 1 disease in newborns with co-infections. Pediatr. Infect. Dis. J. 20, 404-410. 7. Aiken, C.G. (2004) HIV-1 infection and perinatal mortality in Zimbabwe. Arch. Dis. Child. 67, 595-599. 8. Roe, M. et al. (2003) Respiratory viruses in the intensive care unit. Paediatr. Respir. Rev. 4, 166-171. 9. Semple, M.G. et al. (2005) Dual infection of infants by human metapneumovirus and human respiratory syncytial virus is strongly associated with severe bronchiolitis. J. Infect. Dis. 191, 382-386. 10. Sloots, T.P. et al. (2008) Emerging respiratory agents: new viruses for old diseases? J. Clin. Virol. 42, 233-243. P r e l i m i n a r y Michael Nissen (BMedSc, MBBS, FRACP, FRCPA) is director of infectious diseases at the Royal Children’s Hospital, Brisbane, unit director (medical) of the Queensland Paediatric Infectious Diseases (QPID) Laboratory, and clinical microbiologist overseeing the Serology, Virology and Molecular (SVM) Unit of Pathology Queensland Central based at Royal Brisbane Hospital, Brisbane. Michael’s research interests include the characterisation and discovery of respiratory viruses such as WU and KI polyoma viruses, human metapneumovirus, bocavirus, coronaviruses NL-63 and HKU1, and new rhinovirus variants. He is also a chief investigator on three NHMRC project grants including one examining the viral aetiology of indigenous otitis media (OM). Michael was a clinical research associate and post-graduate fellow in the Department of Molecular Microbiology and Pediatrics at the Washington University School of Medicine, St Louis and St Louis Children’s Hospital, USA from 1996-1999, and the recipient of the Connaught Laboratories Inc. Fellowship in Infectious Diseases from the Infectious Diseases Society of America. He currently holds academic appointments with the School of Biomolecular and Physical Sciences, Griffith University, and the Biological and Chemical Sciences Faculty, University of Queensland, Brisbane. Theo Sloots (PhD, GCM, MASM) has more than 25 years’ experience in medical microbiology and is currently the unit director (research) at the Queensland Paediatric Infectious Diseases (QPID) Laboratory of the Royal Children’s Hospital, Brisbane, as well as consultant virologist to Pathology Queensland Central. Research at the QPID Laboratory has focused on examining the significance of human metapneumovirus as a newly recognised respiratory pathogen, and the discovery of new viral agents associated with respiratory disease in children. Theo is a chief investigator on three separate research project grants funded by the NHMRC, and also holds academic appointments with the Biological and Chemical Sciences Faculty, University of Queensland, and the School of Biomolecular and Physical Sciences, Griffith University, Brisbane. A n n o u n c e m e n t IV Mycology MasterClass 2009 Hamilton Island QLD 2009 Friday 30 – Saturday 31 October 2009 Plus: Satellite Workshop for Laboratory Staff – Sunday 1 November 2009 Back by popular demand – places are strictly limited and will sell-out in advance! Mark these dates in your diary now! Registration opens – Feb 2009 Advanced Medical Mycology Course for specialists and trainees in Infectious Diseases, Microbiology, Haematology & Intensive Care Medicine and for Laboratory Scientists/Technicians specialising in Medical Mycology Discount registration available to financial members of ASM, ASID and HSANZ Specially discounted accommodation rates on Hamilton Island have been negotiated for delegates Website Launch – February 2009 Convenor: Associate Professor David Ellis, Mycology Unit – Women’s & Children’s Hospital, Adelaide SA Conference Organisers: Australian Society for Microbiology M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 199 Under the Microscope Pathogenesis of cytomegalovirus (CMV) infection in pregnancy Gillian M Scott, Alicia Steller, Shu Wang, Karen WW Teng and Sharon SW Chow Virology Division, Department of Microbiology SEALS, Prince of Wales Hospital Randwick NSW 2031 School of Biotechnology and Biomolecular Sciences, Faculty of Science and School of Medical Sciences, Faculty of Medicine University of New South Wales NSW 2052 Tel (02) 9382 9096 Fax (02) 9382 8533 Email [email protected] Cytomegalovirus (CMV) infection during pregnancy can have devastating effects on the developing fetus. Maternal CMV infection can affect the fetus in two ways: firstly by transmission to, and replication in, fetal tissue resulting in direct damage to developing organs; or, less well recognised, through cellular changes that potentially affect placentation and transfer of nutrients and gases to the developing fetus. Congenital CMV infections occur in approximately 0.5-2% of births and 10-15% of these infections will be symptomatic, resulting in petechiae, jaundice, hepatosplenomegaly, chorioretinitis or more severe manifestations such as cytomegalic inclusion disease (CID) and stillbirth 1, 2. As such, CMV has become the leading viral cause of congenital malformation in newborns now that rubella vaccination is universally available. More than half of CMV-infected infants who are symptomatic at birth are also at risk of long-term sequelae such as learning difficulties or sensorineural hearing loss 1, 2. Symptomatic congenital infections are usually the result of CMV transmission in the first trimester of pregnancy. Fortunately, a larger percentage of children infected with CMV during pregnancy will remain asymptomatic. Less well recognised is the percentage of miscarriage and preterm births that may result from CMV infections in pregnancy. The reasons for these differences in outcome are unknown, but CMV strain variation, co-infections, host immunity and altered host cellular responses are suspected of playing a role. Congenital CMV infection and maternal immunity CMV infection of the placenta and fetus most often results from primary infection of the mother. CMV transmission is therefore facilitated by an immunologically naïve host, allowing the virus to replicate to high titres in the infected mother, and disseminate and cross the placenta before a sufficient immune response is mounted. Low avidity antibodies with poor neutralising activity 200 are generated following primary CMV infection and the presence of these antibodies in the first 20 weeks of pregnancy is a strong predictor for congenital transmission of CMV 3. Conversely, high avidity antibodies are produced much later through the process of immune maturation but provide greater neutralising ability and protection against CMV transmission. This explains why hyperimmune globulin therapy is able to reduce the incidence of congenital transmission when given to women with primary CMV infections 4. A mature cellular immune response is also important in limiting CMV dissemination and controlling reactivation from latency. Despite this, secondary CMV infections in the mother have also been shown to contribute to a small but significant percentage of congenital transmission, suggesting CMV-specific maternal immunity is not always protective, particularly when a different strain of the virus is acquired 5. These factors have implications for the design of potential vaccines that must protect against infections with different CMV strains and provide a sustained humoral and cellular immune response during pregnancy. A DNA vaccine containing plasmids encoding the CMV pp65 phosphoprotein (a primary target of the host CD4+ and CD8+ T-cell response) and envelope glycoprotein gB (which elicits a strong T-cell response and neutralising antibodies) has recently shown promise in phase I clinical trials in CMV seronegative adults 6. However, like many candidate vaccines before it, enhanced CMV immunity in CMV seropositive individuals could not be achieved. Transplacental transmission of CMV The human placenta is the primary route for transmission of CMV from mother to fetus 7-9. Maternal viraemia can result in spread of virus to the placenta, which serves as a reservoir for CMV replication and subsequent transmission to the fetus. The placenta offers some protection against congenital transmission, MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope consistent with our observations of CMV detection in placenta tissue without concomitant infection of the corresponding fetus or newborn. For CMV congenital infection to occur, the virus must negotiate a complex pathway across the placenta that involves a number of different cell types. The exact process of CMV transplacental transmission is not fully understood, but recent studies are providing valuable insights into the potential mechanisms and transmission routes of virus from mother to fetus. CMV productively infects primary syncytiotrophoblasts in Transmission of congenital CMV is dependent upon passage through specialised cells of the placenta called cytotrophoblasts. These cells have specific functions depending on their location within the placenta. Villous cytotrophoblasts located at the surface of floating chorionic villi act as progenitor cells for the formation of an outer multinucleate syncytiotrophoblast layer. This syncytiotrophoblast layer is in direct contact with maternal blood in the intervillous space and normally acts as a conduit for exchange of nutrients and gases for the developing fetus. Extravillous cytotrophoblasts arrange into columns of anchoring chorionic villi that attach to the uterine wall. Cells at the base of these columns further differentiate to become invasive cytotrophoblasts that enter the interstitium of the uterus and the uterine vasculature, diverting and increasing maternal blood flow to the placenta. Potential transmission routes of CMV across the placenta therefore involve passage through syncytiotrophoblasts of the chorionic floating villi and/or infection of extravillous cytotrophoblasts of anchoring villi. Transmission of infectious virus is dependent on the virion- We typically observe CMV DNA within syncytiotrophoblasts of CMV-infected placentae (Figure 1), with CMV also detected within underlying cytotrophoblasts, stromal cells and endothelial cells lining fetal vessels within the floating chorionic villi 9. This suggests that CMV can enter the fetal circulation by transfer from maternal blood across the syncytiotrophoblast layer to infect underlying cytotrophoblasts, before transmission through the stromal layer to fetal vessels. culture 10, but evidence that active CMV replication occurs within syncytiotrophoblasts in utero is limited. Examination of biopsies taken from early trimester placenta suggests that CMV is transported across the syncytiotrophoblast layer by receptormediated transcytosis of virion-antibody immune complexes utilising the pathway normally used to transfer maternal IgG for passive immunity 11. immune complex containing low avidity, rather than high avidity, antibodies 11. It is hypothesised that virion-immune complexes consisting of high avidity antibodies are transported intact across the syncytiotrophoblast layer, but are endocytosed by macrophages within the chorionic floating villi or internalised by underlying cytotrophoblasts. Conversely, CMV virions in complexes with low avidity antibodies are thought to be released when they reach the cytotrophoblast layer, and therefore able to go on and infect other cells and fetal blood vessels within the chorionic villi. This hypothesis is consistent with the higher incidences of congenital CMV transmissions that occur in the presence of low avidity maternal antibodies 3. Evidence also exists for the transmission of CMV across the placenta through infection of invasive extravillous cytotrophoblasts of the anchoring villi from the maternal decidua . This route also 12, 13 appears to be a complex and lengthy pathway for transplacental transmission of the virus, but may be relevant in the early stages of gestation where the placenta is undergoing rapid changes. The effect of CMV infection on placental development CMV is known to induce changes in the expression of cellular proteins of infected cells and subvert many cellular pathways to Figure 1: CMV localisation in the human placenta. CMV was detected by in situ PCR (purple) in syncytiotrophoblast (ST) cells (purple) lining placental floating villi (FV) (a). In normal pregnancy, the syncytiotrophoblast layer allows for transfer of nutrients from maternal blood in the intervillous space (IVS) to fetal blood vessels (FB). Control in situ PCR carried out on the same tissue demonstrates the reaction is specific for CMV (b). M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 201 Under the Microscope advance or promote viral replication. It is therefore conceivable that CMV infection of the differentiating and supporting cells of the placenta can have deleterious effects on placentation and fetal development. Indeed, there is increasing evidence that CMV infection can indirectly affect the developing fetus by altering the process of placentation and causing pathological changes to the placenta in the early stages of pregnancy. Early cytotrophoblast invasion of the uterine decidua is critical to the establishment and maintenance of a functioning placenta, and a number of proteins are known to be important in this process, including cellular growth factors, integrin receptors and matrix metalloproteinases 14. KAI1, a metastatis suppressor protein, is expressed by decidual cells at the uterine-placental interface, and thought to promote invasion of the endometrium by extravillous cytotrophoblasts 15. We have demonstrated increased expression of KAI1 in the decidua of CMV-infected placenta (Figure 2), suggesting CMV may interfere with the communication between invading fetal cytotrophoblasts and cells of the maternal decidua that is thought to regulate placental development. In addition to this, CMV infection of extravillous cytotrophoblast cells directly interferes with their differentiation towards invasiveness, metalloproteinase-9 secretion and epithelial growth factor expression 16. We are currently investigating the extravillous trophoblast infectivity of low-passage CMV strains isolated from maternal urine and congenitally infected infants to determine the differential effects of strain variation and identify the viral genes essential for replication in cytotrophoblast cells. The role of inflammatory cytokines The role of cytokines in congenital CMV infection is only now being elucidated. Some groups have shown even UV-inactivated CMV can elicit the release of inflammatory cytokines and apoptosis in syncytiotrophoblast cells, suggesting cytokine mediated damage of the syncytiotrophoblast layer as a potential mechanism for CMV infection of placental villi and transmission to the fetus 17. Likewise, changes in fetal cytokine production in response to CMV infection may also have a role in the pathogenesis of CMVinduced fetal damage. We have observed changes in the level of certain pro- and antiinflammatory cytokines, including interleukin-6, in the amniotic fluid of CMV-infected fetuses. These changes have correlated with cytokine expression in extravillous trophoblasts and epithelia of the amniotic membrane (Figure 3). Further experiments are underway to determine whether observed changes in fetallyderived cytokine levels are similar to changes in CMV-infected placental tissue at different stages of gestation, and to correlate these with histopathological tissue damage. Animal models for the study of congenital CMV transmission The investigations of human CMV congenital infection described above are helping to elucidate the mechanisms of transplacental CMV transmission but there are obvious ethical and practical limitations to in vivo studies of human CMV pathogenesis. Human CMV is highly host restricted and will only infect humans and human cell lines, and animal models are therefore required to study CMV infection in vivo. There are many animal homologues of human CMV, but only a few of these have been extensively studied. Guinea pigs and rhesus macaques are similar to humans in terms of placental architecture and congenital CMV infection, but use of these animal models is limited in terms of availability, practicality and what we know about guinea pig and rhesus CMV in general 18, 19. Much more detailed knowledge is available regarding the pathogenesis, immunology and genetics of murine CMV infection in mice 20-22, and murine models are used extensively to advance our understanding of human placental development and other factors affecting pregnancy outcomes 23, 24. Transplacental transmission of murine CMV from immunocompetent mice to fetal pups has not been previously demonstrated, although congenital infection of fetal pups can occur when murine CMV is injected directly to murine placentas 25. Figure 2: Up-regulation of KAI1 protein in CMV-infected tissue at the uterine-placental interface. Increased expression of KAI1 protein (brown) in the decidual cells (D) at the uterine-placental interface of CMV-positive placental tissue (a) compared with CMV-negative tissue (b), as determined by immunohistochemical analysis. The placenta is anchored to the maternal decidua by the fetal anchoring villi (AV). 202 MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope Developments in the small animal models of guinea pig and mice are likely to be seen in the near future. These models will complement ongoing investigations of human CMV and assist with identification of therapies and vaccines for prevention of CMV transplacental transmission and congenital infection. References 1. Ross, S.A. and Boppana, S.B. (2005) Congenital cytomegalovirus infection: outcome and diagnosis. Sem. Ped. Infect. Dis. 16, 44-49. 2. Munro, S.C. et al. (2005) Symptomatic infant characteristics of congenital cytomegalovirus disease in Australia. J. Paed. Child Health 41, 449-452. 3. Lazzarotto, T. et al. (2008) New advances in the diagnosis of congenital cytomegalovirus infection. J. Clin. Virol. 41, 192-197. 4. Boppana, S.B. et al. (2001) Intrauterine transmission of cytomegalovirus to infants of women with preconceptional immunity. New Engl. J. Med. 344,13661371. 5. Nigro, G. et al. (2005) Passive immunization during pregnancy for congenital cytomegalovirus infection. New Engl. J. Med. 2005. 353, 1350-1362. 6. Wloch, M.K. et al. (2008) Safety and immunogenicity of a bivalent cytomegalovirus DNA vaccine in healthy adult subjects. J. Infect. Dis. 197, 1634-1642. 7. Pereira, L. et al. (2005) Insights into viral transmission at the uterine-placental interface. Trends Microbiol. 13, 164-174. 8. Chow, S.S.W. et al. (2006) Correlates of placental infection with cytomegalovirus, parvovirus B19 or human herpes virus. J. Med. Virol. 78, 747-756. 9. Trincado, D.E. et al. (2005) Highly sensitive detection and localization of maternally acquired human cytomegalovirus in placental tissue by in situ polymerase chain reaction. J. Infect. Dis. 192, 650-657. 10. Schleiss, M.R. et al. (2007) Cytomegalovirus infection of human syncytiotrophoblast cells strongly interferes with expression of genes involved in placental differentiation and tissue integrity. Ped. Res. 61, 565-571. 11. Maidji, E. et al. (2006) Maternal antibodies enhance or prevent cytomegalovirus infection in the placenta by neonatal Fc receptor-mediated transcytosis. Am. J. Pathol. 168, 1210-1226. 12. Fisher, S. et al. (2000) Human cytomegalovirus infection of placental cytotrophoblasts in vitro and in utero: implications for transmission and pathogenesis. J. Virol. 74, 6808-6820. 13. Maidji, E. et al. (2002) Transmission of human cytomegalovirus from infected uterine microvascular endothelial cells to differentiating/invasive placental cytotrophoblasts. Virology 304, 53-69. 14. Ferretti, C. et al. (2007) Molecular circuits shared by placental and cancer cells, and their implications in the proliferative, invasive and migratory capacities of trophoblasts. Human Reprod. Update 13, 121-141. 15. Gellersen, B. et al. (2007) Expression of the metastasis suppressor KAI1 in decidual cells at the human maternal-fetal interface: regulation and functional implications. Am. J. Pathol. 170, 126-139. 16. LaMarca, H.L. et al. (2006) Human cytomegalovirus-induced inhibition of cytotrophoblast invasion in a first trimester extravillous cytotrophoblast cell line. Placenta 27, 137-147. 17. Chan, G. and Guilbert, L.J. (2006) Ultraviolet-inactivated human cytomegalovirus induces placental syncytiotrophoblast apoptosis in a Toll-like receptor-2 and tumour necrosis factor-alpha dependent manner. J. Pathol 210, 111-120. 18. Schleiss, M.R. (2002) Animal models of congenital cytomegalovirus infection: an overview of progress in the characterization of guinea pig cytomegalovirus (GPCMV). J. Clin. Virol. 25, S37-49. 19. Kuhn, E.M. et al. (1999) Immunohistochemical studies of productive rhesus cytomegalovirus infection in rhesus monkeys (Macaca mulatta) infected with simian immunodeficiency virus. Vet. Pathol. 36, 51-56. 20. Rawlinson, W.D. et al. (1996) Analysis of the complete DNA sequence of murine cytomegalovirus. J. Virol. 70, 8833-8849. 21. Tsutsui Y. et al. (2005) Neuropathogenesis in cytomegalovirus infection: indication of the mechanisms using mouse models. Rev. Med. Virol. 15, 327345. 22. Smith, L.M., et al. (2008) Laboratory strains of murine cytomegalovirus are genetically similar to but phenotypically distinct from wild strains of virus. J. Virol. 82, 6689-6696. 23. Georgiades, P. et al. (2002) Comparative developmental anatomy of the murine and human definitive placentae. Placenta 23, 3-19. 24. Malassine, A. et al. (2003) A comparison of placental development and endocrine functions between the human and mouse model. Human Reprod. Update 9, 531-539. 25. Li, R.Y. and Tsutsui, Y. (2000) Growth retardation and microcephaly induced in mice by placental infection with murine cytomegalovirus. Teratology 62, 79-85. Dr Gillian Scott completed her PhD on cytomegalovirus antiviral susceptibility and resistance in 2004 and is now a postdoctoral scientist in the Department of Microbiology, SEALS at Prince of Wales Hospital and conjoint lecturer at the University of New South Wales. She has continued her research of CMV susceptibility to current and potential antiviral agents as well as investigations of CMV pathogenesis in liver transplantation and congenital infection. Alicia Steller, Shu Wang and Karen Teng are currently honours students at the University of New South Wales conducting research into CMV congenital infection at Prince of Wales Hospital. Alicia intends to pursue a career in science following completion of her studies, Shu will continue her medical studies at UNSW, and Karen intends to continue as a PhD student next year. Sharon Chow is a UNSW PhD student in the final stages of her studies into maternal and fetal immunological responses to congenital CMV infection. The majority of her research is conducted in the virology research lab at Prince of Wales Hospital under the supervision of Prof William Rawlinson in collaboration with Prof Cheryl Jones from the Children’s Hospital at Westmead. Figure 3: IL-6 expression in amniotic membranes. IL-6 expression (brown) is localised to the extravillous trophoblasts (ET) and amniotic epithelium (AE) of fetal amniotic membranes (a). Immunohistochemistry negative control (no primary antibody) carried out on tissue from the same individual indicates IL-6 detection is specific (b). M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 203 Under the Microscope Pathogenesis of malaria in pregnancy Stephen J Rogerson Steven R Meshnick Department of Medicine (RMH/WH), The University of Melbourne, Post Office Royal Melbourne Hospital Parkville VIC 3050 Tel (03) 8344 3259 Fax (03) 93471863 Email [email protected] Department of Epidemiology, University of North Carolina School of Public Health Chapel Hill, NC USA 27599-7435 Tel (1) 919-966-7414 Fax (1)919-966-0584 Email [email protected] Even though we have good tools to prevent and treat susceptibility to malaria, resulting in more prevalent and higher- malaria, it remains a tragically common disease in poor density infection, and a relative loss of gravidity-dependent countries, especially in Africa. Pregnant women are immunity 8. In low transmission areas, women of all gravidities particularly susceptible to malaria, causing anaemia and are affected. poor birth outcomes. There is marked sequestration of Placental pathology Plasmodium falciparum-infected erythrocytes (IEs) in the placenta, but the pathogenesis of malaria in pregnancy is still incompletely understood. Both intermittent preventive therapy and insecticide-impregnated bed nets are effective protective measures, but new measures are also needed. P. falciparum causes three specific changes in the placenta. IEs containing mature trophozoite and schizont parasite stages accumulate in the intervillous spaces (the lake-like structures through which maternal blood circulates), sometimes to very high densities 9. Placental malaria may be accompanied by intervillous infiltrates of monocytes and macrophages, some containing Epidemiology malaria pigment (hemozoin). Finally, hemozoin may also be seen Malaria causes maternal anaemia and contributes to an estimated 10,000 maternal deaths each year 1. Moreover, malaria infections result in 75,000-200,000 low birth weight babies each year, due to combinations of preterm delivery and fetal growth in fibrin deposits, and these pigmented fibrin deposits can persist after resolution of episodes of infection. Each of these changes (parasites, monocytes, or pigmented fibrin) has been associated with poor birth outcomes. restriction 2, 3. The most dangerous form of malaria for pregnant Sequestration of IE plays an important role in all P. falciparum- women is P. falciparum; P. vivax infections also cause poor associated pathology. In the brain and other viscera, ICAM-1 and birth outcomes . CD36 are the primary ligands for IE. In the placenta, in contrast, 4 Pregnant women are at greater risk of malaria infection and of symptomatic malaria disease than non-pregnant adults for several IE adhere to chondroitin sulphate A (CSA) and hyaluronic acid, which are expressed by syncytiotrophoblast that line the placental intervillous spaces 10, 11. reasons 5. First, they are more attractive to mosquitoes 6. Second, once infected, parasite burdens are higher in pregnant women Placental IE express variant surface antigens (VSAs), which than in non-pregnant adults. This may be because pregnancy mediate cytoadherence. The major VSAs are the PfEMP1 (P. weakens the host immune response to parasites and because falciparum erythrocyte membrane protein 1) receptors, coded large numbers of parasites sequester in the placenta. for by plasmodial var genes. One var gene, var2csa, appears to be responsible for CSA binding. Deletion of var2csa largely or In areas of high transmission, such as much of sub-Saharan Africa, completely abolishes CSA adhesion 12, 13, placental isolates usually malaria is most frequent in first pregnancies , and this gravidity transcribe high levels of var2csa 14, 15, and levels of antibody to dependent susceptibility is a key feature of disease epidemiology. VAR2CSA recombinant proteins correlate with protection in Prevalence of infection peaks early in pregnancy (between some subgroups 16, 17. Thus, VAR2CSA may be a promising vaccine 13-16 weeks) , declining towards term. HIV infection increases candidate. 7 5 204 MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope Malaria may evade the host immune response in the placenta Kinshasa, the effects of malaria were most evident in by altering the response. Placental malaria causes increased undernourished synthesis of inflammatory cytokines like TNF, interleukin-2 and supplementation has been shown to improve birth weight 24, and interferon γ 18-20. Increased placental TNF has been associated it may be that combined nutritional and malaria interventions with low birth weight and anaemia 18, 21. Some of the mechanisms would give optimal fetal protection from growth restriction. by which malaria may result in premature delivery or fetal growth restriction are illustrated in Figure 1 22. mothers 23 . Maternal macronutrient Timing of infection and fetal growth restriction Few studies have attempted to examine the relationship Undernutrition and malaria between malaria infection during pregnancy and pregnancy Maternal nutrition before and during pregnancy is another outcome. Figure 2 illustrates the relationship between important determinant of birth weight. In a recent study in fetal growth, gestation, and timing of currently-used Figure 1. Potential pathogenic mechanisms by which placental malaria affects placental function and results in intrauterine growth retardation or preterm delivery. Reproduced with permission 22. IRBC – infected red blood cell; CSA – chondroitin sulfate A; IUGR – intrauterine growth retardation; PTD – preterm delivery. 0DODULD ,5%& $QHPLD &6$ 5HFHSWRU 2EVWUXFWHGIORZ VHTXHVWUDWLRQ 0DWHUQDO ,PSDLUHGJURZWK YDVFXODUL]DWLRQ 3ODFHQWD )HWDO +\SR[LD 7K&\WRNLQH VWUHVV LQIODPPDWRU\ FHOOV 'HFUHDVHGQXWULHQW XSWDNH ,8*5 )HWDO K\SR[LD 37' /2:%,57+:(,*+7 ASM sustaining members BioMerieux Australia Pty Ltd Abbott Diagnostics Division Oxoid Australia Pty Ltd Wyeth Australia Pty Ltd Millipore Australia Pty Ltd BD Diagnostics Bio Rad Laboratories Diagnostic Technology Don Whitley Scientific Pty Ltd Inverness Medical Innovations Roche Diagnostics Australia Siemens Health Care Diagnostics Blackaby Diagnostics Pty Ltd Corbett Research Department of Primary Industries M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 205 Under the Microscope interventions 22, 25. Presently, it is unknown whether infection early in pregnancy may compromise ultimate fetal growth potential, although one study suggests this may be the case 26. Malaria and the neonate Newborns in areas of high malaria transmission are relatively protected from malaria in early life, although the mechanisms are not fully understood 27, 28. Cord blood infection is commonly detected, especially when sensitive molecular diagnosis is used , but symptomatic neonatal infection is rare in 29, 30 endemic areas 31. Contributing factors may include innate mechanisms (including fetal haemoglobin and p-amino benzoic acid-deficient breast milk), cultural ones (swaddling of newborns, decreasing their exposure), transplacental transfer of protective antibody , 32, 33 and priming of neonatal responses by transplacental transfer Prevention of malaria in pregnant women of parasites or their products 34, 35. In case reports from the US, Effective and affordable ways to protect pregnant women from newborns of non-immune women have developed severe febrile malaria are discussed in the article by Heather Jeffery in this issue. illness due to P. falciparum or P. vivax malaria 36. The apparent Unfortunately, only 2-50% of pregnant women in malaria-endemic rareness of similar cases in babies of semi-immune women area currently sleep under bednets and relatively few women suggests a central protective role for transplacental antibody receive the recommended intermittent preventive treatment , possibly (IPT) 39. Additionally, due to the emergence of resistance, new increasing susceptibility of children of HIV-infected mothers to IPT regimens are needed. Such drugs will need to be evaluated malaria. closely for safety in pregnancy, as well as for efficacy and, because transfer. HIV infection interferes with this process 37,38 Figure 2. Relationship between timing of IPT, fetal growth rates, and potential vulnerability of mother and fetus to deleterious effects of malaria. The fetal growth rate varies over the course of pregnancy, peaking at about 36 weeks (blue curve). In the context of moderate SP resistance, IPTp (vertical green arrows) may or may not clear infection, and offer a shortened period of prophylaxis against reinfection (attached horizontal black arrows) 25. Reinfection during the period of vulnerability may affect fetal growth (double headed arrow). The effects of malaria early in pregnancy (dotted arrow) on fetal growth are less well understood. Reproduced with permission 22. ,37S[ "" 9XOQHUDELOLW\ 206 *HVWDWLRQZHHNV MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope drug pharmacokinetics can change radically in pregnancy, it will be important to ensure optimal dosing regimes. Conclusions Our understanding of the pathogenesis of malaria in pregnancy has improved significantly in recent years, but important gaps remain. Many challenges remain in developing and implementing interventions to protect pregnant women from malaria. A recently inaugurated Malaria in Pregnancy Consortium , funded 40 by the Gates Foundation and EDCTP, will accelerate progress in protecting pregnant women and their infants from malaria. Acknowledgements SJR is supported by the NH&MRC of Australia and by the Malaria in Pregnancy Consortium. SRM is supported by the NIH. We thank Sarah Landis for the prototype of Figure 1. References 1. Guyatt, H.L. et al. (2004) Use of intermittent presumptive treatment and insecticide treated bed nets by pregnant women in four Kenyan districts. Trop. Med. Int. Health. 9, 255-261. 2. Steketee, R.W., et al. (2001) The burden of malaria in pregnancy in malariaendemic areas. Am. J. Trop. Med. Hyg. 64, 28-35. 3. Guyatt, H.L., and Snow, R.W. (2004) Impact of malaria during pregnancy on low birth weight in sub-Saharan Africa. Clin. Microbiol. Rev. 17, 760-769. 4. ter Kuile, F., and Rogerson, S.J. (2008) Plasmodium vivax infection during pregnancy: an important problem in need of new solutions. Clin. Infect. Dis 46, 1382-1384. 5. Brabin, B.J. (1983) An analysis of malaria in pregnancy in Africa. Bull. World Health Org. 61, 1005-1016. 6. Lindsay, S. et al. (2000) Effect of pregnancy on exposure to malaria mosquitoes. Lancet 355, 1972. 7. Brabin, B.J. and Rogerson, S.J. (2001) The epidemiology and outcomes of maternal malaria. In Malaria in Pregnancy. Deadly Parasite, Susceptible Host (Duffy, P.E., and Fried, M., eds), p.27-52, Taylor and Francis. 8. ter Kuile, F.O. et al. (2004) The burden of co-infection with human immunodeficiency virus type 1 and malaria in pregnant women in sub-saharan Africa. Am. J. Trop. Med. Hyg.71, 41-54. 9. Brabin, B.J. et al. (2004) Dapsone therapy for malaria during pregnancy: maternal and fetal outcomes. Drug Saf. 27, 633-648. 10. Salem, H.H. et al. (1984) Isolation and characterization of thrombomodulin from human placenta. J. Biol. Chem. 259, 12246-12251. 11. Matejevic, D. et al. (2001) Localization of hyaluronan with a hyaluronan-specific hyaluronic acid binding protein in the placenta in pre-eclampsia. Gynecol. Obstet. Invest. 52, 257-259. 12. Viebig, N.K. et al. (2005) A single member of the Plasmodium falciparum var multigene family determines cytoadhesion to the placental receptor chondroitin sulphate A. EMBO Rep. 6, 775-781. 13. Duffy, M.F., et al. (2006) VAR2CSA is the principal ligand for chondroitin sulfate A in two allogeneic isolates of Plasmodium falciparum. Mol. Biochem. Parasitol. 148, 117-124. 14. Tuikue Ndam, N.G. et al. (2005) High level of var2csa transcription by Plasmodium falciparum isolated from the placenta. J. Infect. Dis. 192, 331335. 20. Moormann, A.M. et al. (1999) Malaria and pregnancy: placental cytokine expression and its relationship to intrauterine growth retardation. J. Infect. Dis. 180, 1987-1993. 21. Rogerson, S.J. et al. (2003) Placental monocyte infiltrates in response to Plasmodium falciparum infection and their association with adverse pregnancy outcomes. Am. J. Trop. Med. Hyg. 68, 115-119. 22. Rogerson, S.J., Mwapasa, V. and Meshnick, S.R. (2007) Malaria in pregnancy: linking immunity and pathogenesis to prevention. Am. J. Trop. Med. Hyg. 77(6_Suppl): 14-22. 23. Landis, S.H. et al. (2008) Impact of maternal malaria and under-nutrition on intrauterine growth restriction: a prospective ultrasound study in Democratic Republic of Congo. Epidemiol. Infect. 1-11. 24. Ceesay, S.M. et al. (1997) Effects on birth weight and perinatal mortality of maternal dietary supplements in rural Gambia: 5 year randomised controlled trial. BMJ 315, 786-790. 25. Anonymous (2005) World Malaria Report, 2005. Unicef/Roll Back Malaria/ WHO. 26. Cottrell, G. et al. (2005) Is malarial placental infection related to peripheral infection at any time of pregnancy? Am. J. Trop. Med. Hyg.73, 1112-1118. 27. Wagner, G. et al. (1998) High incidence of asymptomatic malaria infections in a birth cohort of children less than one year of age in Ghana, detected by multicopy gene polymerase chain reaction. Am. J. Trop. Med. Hyg. 59, 115123. 28. Riley, E.M. et al. (2001) Do maternally acquired antibodies protect infants from malaria infection? Parasite Immunol. 23, 51-59. 29. Tobian, A.A. et al. (2000) Frequent umbilical cord-blood and maternal-blood infections with Plasmodium falciparum, P. malariae, and P. ovale in Kenya. J. Infect. Dis.182, 558-563. 30. Kamwendo, D.D. et al. (2002) Plasmodium falciparum: PCR detection and genotyping of isolates from peripheral, placental, and cord blood of pregnant Malawian women and their infants. Trans. Royal Soc. Trop. Med. Hyg. 96, 145149. 31. Fischer, P.R. (2003) Malaria and newborns. J. Trop. Pediat. 49, 132-134. 32. Branch, O.H. et al. (1998) A longitudinal investigation of IgG and IgM antibody responses to the merozoite surface protein-1 19-kiloDalton domain of Plasmodium falciparum in pregnant women and infants: associations with febrile illness, parasitemia and anemia. Am. J. Trop. Med. Hyg. 58, 211-219. 33. Hviid, L. and Staalsoe, T. (2004) Malaria immunity in infants: a special case of a general phenomenon? Trends Parasitol. 20, 66-72. 34. Malhotra, I. et al. (2005) Distinct Th1- and Th2-Type prenatal cytokine responses to Plasmodium falciparum erythrocyte invasion ligands. Infect. Immunity 73, 3462-3470. 35. King, C.L. et al. (2002) Acquired immune responses to Plasmodium falciparum merozoite surface protein-1 in the human fetus. J Immunol 168, 356-364. 36. Hulbert, T.V. (1992) Congenital malaria in the United States: report of a case and review. Clin Infect Dis 14, 922-926. 37. de Moraes-Pinto, M.I. et al. (1996) Placental transfer and maternally acquired neonatal IgG immunity in human immunodeficiency virus infection. J. Infect. Dis. 173, 1077-1084. 38. de Moraes-Pinto, M.I. et al. (1998) Placental antibody transfer: influence of maternal HIV infection and placental malaria. Arch. Dis. Childhood 79, F202205. 39. White, N.J. (2005) Intermittent presumptive treatment for malaria. PLoS Med. 2, e3. 40. http://www.mip-consortium.org/ 15. Duffy, M.F. et al. (2006) Transcribed var genes associated with placental malaria in Malawian women. Infect. Immun. 74, 4875-4883. 16. Salanti, A. et al. (2004) Evidence for the involvement of VAR2CSA in pregnancyassociated malaria. J. Exp. Med. 200, 1197-1203. 17. Tuikue Ndam, N.G. et al. (2006) Dynamics of anti-VAR2CSA immunoglobulin G response in a cohort of Senegalese pregnant women. J. Infect. Dis. 193, 713-720. 18. Fried, M. et al. (1998) Malaria elicits type 1 cytokines in the human placenta: IFN-g and TNF-a associated with pregnancy outcomes. J. Immunol. 160, 2523-2530. 19. Moore, J. et al. (1999) Immunity to placental malaria. I. Elevated production of interferon-g by placental blood mononuclear cells is associated with protection in an area with high transmission of malaria. J. Infect. Dis. 179, 1218-1225. M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 Steven Meshnick is professor of epidemiology and of microbiology and immunology at the University of North Carolina, Chapel Hill, USA. He uses molecular epidemiology to understand the prevention and pathogenesis of malaria in pregnancy, antimalarial drug resistance and HIV mother-to-child transmission. Stephen Rogerson is associate professor in the Department of Medicine, University of Melbourne. His research interests include the pathogenesis, immunity and prevention of malaria in pregnancy, and the interaction between HIV and malaria infections. 207 In Focus Goal setting and reality: maternal, perinatal and childhood malaria Parasites and transmission Heather Jeffery School Public Health Edward Ford Building University of Sydney & Royal Prince Alfred Hospital Newborn Care, Sydney NSW Tel 0402 223 840 Email [email protected] The protozoan, viral and bacterial infections of malaria, human immunodeficiency virus (HIV) and tuberculosis (TB) cause over 5.5 million deaths each year 1. This burden of disease is largely concentrated in the same geographical regions, related to vector distribution, their association with poverty and the vulnerability of HIV infected people to both malaria and TB. This paper is a review of the devastating effects of malaria in the most susceptible hosts – pregnant women and children. Importantly, a recent technical report from the WHO indicates that rapid coverage and sustained efforts with evidence-based interventions would have a major impact on reducing malarial mortality and morbidity in a relatively short time. Global eradication will require newly developed tools and research directed to prevention, diagnosis and treatment 2. Epidemiology Malaria in pregnancy is a major cause of maternal and perinatal infection, death and morbidity. In low income countries, most deaths in 2002 (>1 million) occurred in children less than 5 years and accounted for over 90% of all malarial deaths 1 and approximately 10% of the 10.6 million deaths in children of this age 3. A recent systematic analysis of maternal deaths in a tertiary referral hospital in Maputo, Mozambique, challenges global estimates that most maternal deaths are attributable to direct, pregnancy-related causes. The authors conducted a prospective study (2002-2004) of 139 of the 179 maternal deaths and found that infectious diseases accounted for half of all deaths and included malaria, HIV and TB 4. An estimated 50 million pregnancies and more than 40% of all births worldwide occur in endemic malarious areas of the tropics and subtropics, including most tropical regions of sub-Saharan Africa, south-east Asia and Latin America 5. 208 Malaria is caused by an intracellular protozoan parasite of the genus Plasmodium. Five species infect humans – P. falciparum, P. vivax, P. ovale, P. malariae and the morphologically similar P. knowlesi. Infected female Anopheles mosquitoes transmit malaria parasites person-to-person and are more attracted to pregnant than non-pregnant women 6. Increased recognition of vertical transmission from mother to fetus either during pregnancy or delivery has been documented in endemic areas with a prevalence rate of up to 32% 7. Spread can also occur from transfusion of infected blood or via infected needles. Transmission of malaria by breast feeding does not occur. P. falciparum is the most lethal malarial parasite with mortality and morbidity concentrated on pregnant mothers and young children, due to the severity of syndromes such as cerebral malaria, pulmonary oedema and profound anaemia 8, 9. Secondary effects of maternal malaria include suppression of immune responses to vaccination, e.g. tetanus toxoid, and reduction in placental transfer of specific antibodies to the fetus, e.g. respiratory syncytial virus, measles, pneumococcus 8. Maternal, perinatal and childhood morbidity and mortality Pregnant women in endemic (stable or high transmission) areas are usually asymptomatic but develop anaemia and, if severe, both maternal morbidity and mortality may be increased. The risk of adverse maternal and perinatal outcome is greater during first pregnancies, younger age and for all gravida women who are HIV positive 10. In epidemic (unstable or low transmission) areas, consequences of infection are more severe and the risk is similar across parity. Non-immune pregnant women are at high risk of cerebral malaria, hypoglycaemia, pulmonary oedema, severe haemolytic anaemia and perinatal death 11. Risk of stillbirth may be increased seven-fold in unstable areas 12. Symptoms and signs (fever, chills, headache, sweats, vomiting) are non-specific. Adverse effects on pregnancy (anaemia) and pregnancy outcomes (stillbirth, abortion, low birth weight (LBW), prematurity, intrauterine growth reduction (IUGR), perinatal mortality, infant anaemia) are directly related to the extent of placental malaria and partly to the degree of maternal anaemia and fever 11, 13, 14. Congenital malaria may present as fever, anaemia, jaundice, hepatosplenomegaly and early death 15. The morbidity due to malaria is extensive, as LBW, IUGR and preterm infants are at increased risk of neonatal death and impaired cognitive development attributable to prenatal and MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 In Focus postnatal causes. Included in the latter are unrecognised and untreated hypoglycaemia in resource poor settings. Further, approximately 7% of children who survive cerebral malaria due to P. falciparum have permanent neurological impairment and others have learning difficulties which adversely affect school performance 16. Similarly, recurrent fever and anaemia due to malaria are exacerbated by drug resistance so that children remain parasitaemic and anaemic, contributing to ill health and impaired school performance. susceptibility of pregnant women to malaria 19. Placental malaria Placental malaria accuracy 21. Additionally, several laboratory tests exist; most In malaria-endemic areas, placental malaria, characterised by parasitised red cells in placental blood in the intervillous space, is a more common finding than parasites in the peripheral circulation of the mother, who is often asymptomatic due to acquired partial immunity. The only species shown to colonise the placenta is P. falciparum. A search for biomarkers to identify placental inflammation has so far established that maternal peripheral blood level of interleukin-10 at a cut off of 15pg/mL has 80% sensitivity and 84% specificity to detect placental malaria 17. Severe maternal and neonatal mortality and sequelae are related to placental inflammation due to malaria 18. The parasitised cells in the placenta express unique variant surface antigens and lack of immunity to these antigens, combined with acquired changes in cell mediated immunity in pregnancy, explain some of the also increases the risk of mother-to-child HIV transmission, emphasising the role of malarial prevention for both malaria and HIV infection in improving perinatal and infant outcomes 20. Diagnosis Light microscopy of thick and thin Giemsa-stained blood smears is the gold standard for diagnosis. Further, rapid antigen detection provide rapid results in 2-10 minutes, with variable accurate and most expensive are tests using PCR to detect parasite nucleic acids. Finally, serology detects antibodies indicating past infection, either by indirect immunofluorescence (IFA) or ELISA. Treatment Prompt appropriate treatment of pregnant women with malaria requires early and effective case management in malarious areas together with screening and appropriate treatment of anaemia. Increasing resistance to efficacious drugs with a well established safety profile in pregnancy such as sulfadoxine-pyrimethamine has led to recommendations that artemisinin combination therapy (ACTs) are the most cost-effective strategy for control of malaria in sub-Saharan Africa 22. Their effect is rapid and reliable, Figure 1. In-patient malaria cases, out-patient laboratory-confirmed cases and in-patient non-malaria cases by month, all ages 2001-2007, Rwanda 33. M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 209 In Focus with >95% efficacy for artesunate-mefloquine, artemetherlumefantrine and dihydroartemisinin-piperaquine 23. (RR 0.62, 95% CI 0.50-0.78), LBW (RR 0.55, 95% CI 0.43-0.70) and perinatal death (RR 0.73, 95% CI 0.53-0.99) 28. In pregnancy, when malaria is uncomplicated, WHO currently recommends ACTs as first choice for second and third trimesters (and if breast feeding) and oral quinine for 7 days in the first trimester 24, 25. CDC updates treatment options, depending on location, for non-immune travellers 26. Recent research has similarly shown that treatment of infants at the time of routine immunisation at 2, 3 and 9 months reduced clinical malarial episodes by 60% and severe anaemia by 50% 29. Current recommendations include use of sulfadoxinepyrimethamine with close monitoring of safety for infants where the burden of disease is high and drug resistance low 30. Prevention Non-immune pregnant women are advised to avoid malaria endemic areas. In general, chemoprophylaxis is not recommended in areas with <10 reported cases of P. falciparum malaria per 1000 inhabitants per year 27. In endemic areas in Africa, WHO recommends a triple approach (the first three points below) for prevention and control in pregnant women 24. Intermittent preventive treatment (IPT) Intermittent preventive treatment (IPT) of at least two doses of antimalarial drugs should be given to all pregnant women at antenatal visits in areas of stable transmission. The relative risk (RR) of routine chemoprophylaxis (such as sulfadoxinepyrimethamine) for pregnant women (low parity) in endemic malarial areas indicates significant reduction in severe anaemia Insecticide-treated bed nets (ITNs) Insecticide-treated bed nets (ITNs) are recommended as early in pregnancy as possible and postpartum 24. In pregnant women in Africa, ITNs reduced placental malaria in all pregnancies (RR 0.79, 95% CI 0.63-0.98). They also reduced LBW (RR 0.77, 95% CI 0.610.98) and fetal loss in the first to fourth pregnancy (RR 0.67, 95% CI 0.47-0.97) 31. ITNs are highly effective in reducing childhood morbidity and all cause mortality from malaria by 20% and halve episodes of malaria 32. About 5.5 lives can be saved each year for every 1000 children protected with ITNs. This equates to 0.5 million child deaths prevented each year in sub Saharan Africa. Recent review of investment in malaria control in four African countries found strong initial evidence that the combined effect of long-lasting insecticidal-treated bed nets (LLINs) and ACTs to Figure 2. In-patient malaria and non-malaria cases in children <5 years old, January 2001 – November 2007, 19 in-patient facilities, Rwanda 33. 210 MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 In Focus all children <5 and all households was associated with a >50% decline of inpatient malaria deaths in Rwanda (66% reduction children <5 years) and Ethiopia (51%) (Figures 1 & 2) 33. Case management Case management and appropriate treatment for febrile malaria and anaemia (see treatment). Prevention/prophylaxis for pregnant travellers The CDC also recommends prevention/prophylaxis for pregnant travellers 34 and lists drugs that are safe and those that are unsafe in pregnancy 35. Vaccines stable and unstable transmission in Ethiopia during a non-epidemic year. J. Inf. Dis. 187, 1765-1772. 13. Steketee, R.W. (2003) Pregnancy, nutrition and parasitic diseases. J. Nutr. 133, 1661S-1667S. 14. Poespoprodjo, J.R. et al. (2008) Adverse pregnancy outcomes in an area where multidrug-resistant Plasmodium vivax and Plasmodium falciparum infections are endemic. Clin. Infect. Dis. 46, 1374-1381. 15. Fischer, P.B. (2003) Malaria and newborns. J. Trop. Ped. 49, 132-134. 16. Holding, P.A. et al. (1999) Cognitive sequelae of severe malaria with impaired consciousness. Trans. Royal Soc. Trop. Med. Hyg. 93, 529-534. 17. Kabyemela, E.R et al. (2007) Maternal peripheral blood level of IL-10 as a marker for inflammatory placental malaria. Malaria J. 7, 26-32. 18. Brabin, B. et al. (2004) The sick placenta: the role of malaria. Placenta 25, 359378. 19. Rogerson, S.J. et al. (2007) Malaria in pregnancy: linking immunity and pathogenesis to prevention. Am. J. Trop. Med. Hyg. 77, 14-22. 20. Brambhatt, H. et al. (2008) J. AIDS 47, 472-476. The difficulties associated with mosquito control and drug resistance to the parasite, together with the large burden of disease due to malaria, have provoked intense research for a suitable vaccine. Currently there is no effective, licensed vaccine, although phase III trials are underway 8, 36. The pre-erythrocytic vaccine RTS,S has demonstrable protection against severe malaria in children for 18 months and clinical malaria episodes in adults 37. 23. Nosten, F. and White, N.J. (2007) Artemisinin-based combination treatment of falciparum malaria. Am. J. Trop. Med. Hyg. 77, 181-192. Conclusion 26. www.cdc.gov/travel The global public health need, attributable to the economic and social burden of malaria 38, the current situation and the research and development needs are outlined by Guerin et al. 36. Research to address the disease burden, in children and pregnant women in particular, vector control, vaccine development, deployment of rapid tests adapted to field situations and effective combination drugs are essential priorities to reduce malaria and prevent escalation of the disease 36. References 1. Revised Global Burden of Disease (GBD) 2002 Estimates. World Health Report 2004. http://www.who.int/healthinfo/bodgbd2002revised/en/index.html 2. Global Malaria control and elimination: report of a technical review. World Health Organisation 2008, p.1-47. 3. Bryce, J. et al. (2005) WHO estimates of the causes of death in children. Lancet 365, 1147-1152. 4. Menendez, C. et al. (2008) An autopsy study of maternal mortality in Mozambique: the contribution of infectious diseases. PloS Medicine 5, e44e47. 5. Steketee, R. et al. (2001) The burden of malaria in pregnancy in malariaendemic areas. Am. J. Trop. Med. Hyg. 64, 28-35. 6. Lindsay, S. et al. (2000) Effect of pregnancy on exposure to malaria mosquitoes. Lancet 355, 1972. 7. Menendez, C. and Mayor, A. (2007) Congenital malaria: the least known consequence of malaria in pregnancy. Sem. Fetal Neonatal Med. 12, 207-213. 8. Duffy, P.E. (2003) Maternal immunization and malaria in pregnancy. Vaccine 21, 3358-3361. 9. Planche, T. and Krishna, S. (2005) The relevance of malaria pathophysiology to strategies of clinical management. Curr. Opin. Inf. Dis. 1895, 369-375. 10. ter Kuile, F. et al. (2004) The burden of co-infection with human immunodeficiency virus type 1 and malaria in pregnant women in sub-Saharan Africa. Am. J. Trop. Med. Hyg. 71, 41-54. 11. van Geertruyden, J.-P. et al. (2004) The contribution of malaria in pregnancy to perinatal mortality. Ann. Trop. Med. Hyg. 71, 35-40. 21. http://www.wpro.who.int/rdt 22. Morel, C. et al. (2005) Cost effectiveness analysis of strategies to combat malaria in developing countries. BMJ, DOI:10.1136/bmj.38639.702384.AE. 24. World Health Organisation (2004) A strategic framework for malaria prevention and control during pregnancy in the African region. Brazzawille: WHO Regional Office for Africa, AFR/MAL/04/01. 25. WHO Guidelines for the treatment of malaria 2006. http://www.who.int/ malaria/docs/TreatmentGuidelines2006.pdf 27. Petersen, E. (2004) Malaria chemoprophylaxis: when should we use it and what are the options? Exp. Rev. Antiinfective Ther. 2, 119-132. 28. Garner P and Gülmezoglu AM. (2002) Drugs for preventing malaria in pregnant women. Cochrane Database Syst. Rev. 2006, Issue 3. Art. No.: CD000169. DOI: 10.1002/14651858.CD000169.pub2 29. Schellenberg, D. et al. (2001) Intermittent treatment for malaria and anaemia control at time of routine vaccinations in Tanzanian infants: a randomised, placebo-controlled trial. Lancet 357, 1471-1477. 30. WHO Report of the technical expert group meeting on intermittent preventive therapy in infancy, Geneva, 2007, p.1-12. 31. Gamble, C. et al. (2006) Insecticide-treated nets for preventing malaria in pregnancy. Cochrane Database Syst. Rev., Issue 2. Art. No.: CD003755. DOI: 10.1002/14651858.CD003755.pub2 32. Lengeler, C. (2004) Insecticide-treated bed nets and curtains for preventing malaria. Cochrane Database Syst. Rev. Issue 2. Art No.: CD000363.pub2. DOI:10.1002/14651858.CD000363.pub2. 33. WHO Global Malaria Program Surveillance, Monitoring and Evaluation Unit. (2008) Impact of long-lasting insecticidal-treated nets and artemisinin-based combination therapies measured using surveillance data in four African countries. 34. http://www.cdc.gov/malaria/risk_map/ 35. http://wwwn.cdc.gov/travel/contentMalariaPregnantPublic.aspx 36. Guerin, P. et al. (2002) Malaria: current status of control, diagnosis, treatment, and a proposed agenda for research and development. Lancet Infect. Dis. 2, 564-573. 37. Graves, P. and Gelband, H. (2002) Vaccines for preventing malaria (preerythrocytic). Cochrane Database Syst. Rev. 2006, Issue 4. Art. No.: CD006198. DOI: 10.1002/14651858.CD006198 38. Sachs, J. and Malaney, P. (2002) The economic and social burden of malaria. Nature 415, 680-685. Heather Jeffery (PhD, MPH, MBBS, FRACP) has had extensive experience as a clinical neonatologist and more recently trained and worked in maternal and perinatal public health in middle and low-income countries. She has wideranging experience with perinatal and childhood malaria in the endemic regions in Malaysia in the 1980s. She currently is professor of international maternal and child health, School of Public Health, University of Sydney. 12. Newman, R.D. et al. (2003) Burden of malaria during pregnancy in areas of M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 211 In Focus Infection and preterm birth Vaginal flora Helen McDonald Women’s & Children’s Hospital 72 King William Road North Adelaide SA 5006 Tel (08) 8161 6725 Email [email protected] Preterm birth (PTB) before 37 weeks’ gestation remains an important cause of perinatal morbidity and mortality, despite modern advances in obstetric and neonatal care. The causes of spontaneous PTB are multi-factorial; however, infection has been implicated as a significant cause of both PTB and late miscarriage, often with no visible signs or symptoms. The most common source for microorganisms gaining access to the uterine cavity and placenta is the lower genital tract, although it is unclear under what circumstances these organisms ascend into the amniotic cavity causing preterm labour, often with chorioamnionitis. It is thought preterm labour may also be initiated by a cascading cytokine host response to vaginal pathogens. Abnormal vaginal flora is more likely to cause ascending infection and preterm labour than normal lactobacillary flora. Bacterial vaginosis (lack of normal vaginal lactobacilli with overgrowth of mixed anaerobic bacteria) in early pregnancy has been consistently associated with a two-fold or more increase in PTB rate. Since antibiotic treatment usually eradicates bacterial vaginosis, a number of randomised, controlled trials have been undertaken to determine whether treatment during early/mid-pregnancy would lower the PTB rate. However, meta-analysis of these trials showed that treatment, while effectively eradicating bacterial vaginosis, failed to decrease the risk of PTB. Studies indicate that treatment earlier in pregnancy may be more successful. Other vaginal microorganisms, such as genital mycoplasmas, have also been implicated in adverse pregnancy outcome. Group B Streptococcus and Escherichia coli are well-known causes of neonatal sepsis, and group B Streptococcus is a major pathogen in unexplained late miscarriage. Recent studies have focused on identifying women who are at highest risk of infectionassociated PTB, for whom preventive treatment may be more beneficial. Genetic studies have identified gene polymorphisms in immunoregulatory genes which influence susceptibility to chorioamnionitis and PTB. Maintenance/restoration of normal lactobacillary flora is important in prevention of PTB. 212 The vaginal flora constitutes a dynamic and complex ecosystem, with many different aerobic and anaerobic organisms present at any one time and at different concentrations. Lactobacillus spp., including the important hydrogen peroxide-producing lactobacilli, are the dominant species in normal vaginal flora, maintaining the vaginal pH between 4.0-4.5. During pregnancy the vaginal flora changes as a result of the substantial hormone increases during the first trimester; the concentration of lactobacilli is ten-fold higher in pregnant women. Microbiological findings in preterm labour Comprehensive case-control studies revealed that two groups of bacteria, bacterial vaginosis organisms (Gardnerella vaginalis and Bacteroides spp.), and an enteropharyngeal group (E. coli, Klebsiella spp. and Haemophilus influenzae/parainfluenzae), were significantly more common in the genital tract of women in preterm labour (often with chorioamnionitis) than labour at term 1-3 (Table 1). In placental and amniotic fluid studies, these and other pathogens such as Group B Streptococcus were significant causes of chorioamnionitis 4, and Group B Streptococcus and E. coli are well-known as major causes of neonatal sepsis. Ureaplasma urealyticum is more common in women with ruptured membranes, and is a cause of chronic respiratory disease in very low birth weight neonates 5. The earlier the gestation of PTB, the stronger are the statistical associations between these organisms and adverse pregnancy outcome. Invasive maternal infection with Listeria monocytogenes is known to carry a high risk of preterm labour, although the pathogenesis is not due to ascending lower genital tract flora but is generally bloodborne from gastrointestinal infection. Microbiological findings in early pregnancy and risk of PTB Prospective vaginal flora studies of women in early pregnancy have shown significant associations between carriage of certain microorganisms and increased risk of PTB and preterm prelabour rupture of membranes 6 (Table 1). The most consistent finding has been the association between PTB and bacterial vaginosis (or bacterial vaginosis organisms) in early pregnancy 7, 8. Unlike the findings of studies in labour, there was no association between vaginal carriage of enteropharyngeal organisms in early pregnancy and increased risk of PTB 9. Symptomatic bacterial vaginosis is characterised by a grey, watery vaginal discharge, often with a fishy odour. Microbiologically, bacterial vaginosis is described as an imbalance of vaginal flora with a reduction or absence of lactobacilli, and an overgrowth of mixed anaerobic flora, including G. vaginalis and often Mycoplasma hominis and Mobiluncus spp. (Figure 1). However, 50% of pregnant women with bacterial vaginosis are asymptomatic. Why these organisms multiply, many of which are normally present in small concentrations in the vagina, while the usually prevalent MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 In Focus lactobacilli decrease, is not clear. The role of hydrogen peroxideproducing lactobacilli appears to be important in preventing overgrowth of anaerobes in normal vaginal flora 10. Other organisms in pregnancy have also been associated with increased risk of PTB and adverse pregnancy outcome such as heavy vaginal carriage/overgrowth of group B Streptococcus 11, M. hominis 12 (usually with bacterial vaginosis present), Trichomonas vaginalis 13 and cervical Chlamydia trachomatis 12 and Neisseria gonorrhoeae. It has been known for many decades that asymptomatic bacteriuria is associated with adverse pregnancy outcome 14. Screening and treatment for asymptomatic bacteriuria at the first antenatal visit is routine in obstetric protocols in the western world. However, Candida albicans is not associated with increased risk of adverse pregnancy outcome. Intervention studies To determine if the risk of infection-associated PTB can be reduced, many studies of antibiotic treatment of bacterial vaginosis, using metronidazole or clindamycin during early to mid-pregnancy, have been undertaken. The Cochrane Database of Systematic Reviews 15 reports a meta-analysis of randomised, placebo-controlled trials of antibiotic treatment of bacterial vaginosis in pregnancy. Although antibiotic therapy was effective in eradicating bacterial vaginosis, there was little evidence that screening and treating all pregnant women with asymptomatic bacterial vaginosis would prevent PTB and its consequences. The gestation of treatment (early rather than mid pregnancy) appears to be important. In the five trials using treatment before 20 weeks, the use of antibiotics showed a significant reduction in risk of PTB 15. It is known that women with a previous PTB are at higher risk of a subsequent PTB. Screening and treatment for bacterial vaginosis in early pregnancy has been advocated in these women since several trials have shown a significant reduction in PTB in this group. Although a recent meta-analysis did not confirm this, there was a reduction in the risk of preterm prelabour rupture of membranes in two trials 15. Intermediate vaginal flora Recent studies have focused on women with abnormal or ‘intermediate’ vaginal flora (by Gram-stain microscopy) not fitting the description of bacterial vaginosis. This intermediate flora is characterised by a reduction in normal lactobacilli, but overgrowth is by aerobic facultative pathogens not usually found in bacterial vaginosis 16 (mainly group B streptococci or occasionally intestinal microorganisms such as E. coli, enterococci). Unlike bacterial vaginosis, vaginal leukocytosis is present. Several studies have shown an increased risk of adverse pregnancy outcome in women with intermediate flora. Two trials of antibiotic treatment of women with intermediate flora in early pregnancy found a significantly lower risk of PTB before 37 weeks 15. Table 1. Vaginal microorganisms and adverse pregnancy outcome. Organism Risk of preterm birth: Sampled in Sampled in midtrimester labour Risk of preterm prelabour rupture of membranes: Sampled in Sampled in midtrimester labour Bacterial vaginosis ++ ++ + G. vaginalis* + + Bacteroides / Prevotella spp.* ++ + M. hominis* + U. urealyticum + Group B Streptococcus* + +/– +/– +† E. coli + Klebsiella spp. + + H. influenzae ∆ +/– +/– C. trachomatis + + N. gonorrhoeae + + T. vaginalis + + Asymptomatic bacteriuria ++ +/– +/–, +, ++ General indication of strength of association and/or number of studies with significant findings * When present in heavy concentrations † In late miscarriage ∆ Cause of amnionitis but uncommon M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 213 In Focus Midtrimester miscarriage The association between intra-uterine infection and late miscarriage (16-24 weeks’ gestation) has been largely unrecognised. In a study of placentas and fetuses in unexplained late miscarriage, group B Streptococcus was the most significant pathogen recovered, especially in women with intact membranes 17. The remaining spectrum of microorganisms recovered was similar to that found in preterm labour at later gestations such as bacterial vaginosis organisms (Bacteroides/Prevotella spp., G. vaginalis), S. anginosus and U. urealyticum. There were no clinical signs suggestive of infection in 70% of women in this study, yet microorganisms were found in 62% of cases (placenta and/or fetus), and 61% had histological evidence of chorioamnionitis. Identification of women at high risk of PTB Since the host response to the presence of microorganisms may vary, studies of cytokine/inflammatory responses have been undertaken. Women with immunoregulatory gene polymorphisms which affect their inflammatory response to certain microorganisms may be at increased risk of adverse pregnancy outcome. Studies of cytokine gene polymorphisms have shown interleukin-10 (IL-10 -1082A/-819T/-592A) and mannose binding lectin (MBL2 codon 54Asp) single nucleotide polymorphisms were independently associated with histological chorioamnionitis and PTB before 29 weeks 18. Pregnant women with periodontal disease may have a higher risk of PTB due to the potential to seed the bloodstream with mouth flora 19. closely related Lactobacillus species of the vagina. Studies of changes in vaginal flora after treatment with metronidazole showed L. iners was the first Lactobacillus to colonise the vagina post treatment 21, suggesting L. iners is a dominant part of the vaginal flora when the flora is in a transitional stage. Further studies using molecular tools are needed to elucidate the role of Lactobacillus species in maintaining normal vaginal flora. Studies of the effects of Lactobacillus phages which may decimate Lactobacillus populations, are also needed. Treatment of bacterial vaginosis may require not only antibiotics capable of eradicating anaerobic bacteria but also Lactobacillus suppositories 22 to re-establish the normal flora, so essential in preventing infectionassociated PTB. References 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Maintenance of normal lactobacillary flora 11. Maintenance of normal lactobacillary flora is of primary importance to a healthy vagina and reduction of PTB. Studies of Lactobacillus species indicate L. crispatus, L. iners, L. gasseri and L. jensenii are most likely to be part of the normal flora in a healthy vagina 20. L. iners deserves close scrutiny, as it was not found in earlier studies due to its peculiar culture requirements, and phenotypic methods have not been able to separate the 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. Figure 1. Gram-stain of bacterial vaginosis including Mobiluncus (Gram-variable curved rods). 214 McDonald, H.M. et al. (1991) Vaginal infection and preterm labour. Br. J. Obstet. Gynaecol. 98, 427-435. Krohn, M.A. et al. (1997) Vaginal colonization by Escherichia coli as a risk factor for very low birth-weight delivery and other perinatal complications. J. Infect. Dis. 175, 606-610. Krohn, M.A. et al. (1991) Vaginal Bacteroides species are associated with preterm delivery in women with preterm labour. J. Infect. Dis. 164, 88-93. Hillier, S.L. et al. (1991) Microbiologic causes and neonatal outcomes associated with chorioamnion infection. Am. J. Obstet. Gynecol. 165, 955-961. Kafetzis, D.A. et al. (2004) Maternal colonization with Ureaplasma urealyticum promotes preterm delivery: association of the respiratory colonization or premature infants with chronic lung disease and increased mortality. Clin. Infect. Dis. 39, 1113-1122. McDonald, H.M. (1997) The role of vaginal flora in normal pregnancy and in preterm labor. In Preterm Labour, (Murdo, E. G., Lamont, R.F. and Romero, R., eds) p.65-83. Hillier, S.L. et al. (1995) Association between bacterial vaginosis and preterm delivery of a low-birth-weight infant. The Vaginal Infections and Prematurity Study Group. New Engl. J. Med. 333, 1737-1742. McDonald, H.M. et al. (1992) Prenatal microbiological risk factors associated with preterm birth. Br. J. Obstet. Gynecol. 99, 190-196. McDonald, H.M. et al. (1994) Changes in vaginal flora during pregnancy and association with preterm birth. J. Infect. Dis. 170, 724-728. Hillier, S.L. et al. (1993) The normal vaginal flora, H2O2-producing lactobacilli and bacterial vaginosis in pregnant women. Clin. Infect. Dis. 16(Suppl 4), S273-281. Regan, J.A. et al. (1996) Colonization with group B streptococci in pregnancy and adverse outcome. VIP Study Group. Am. J. Obstet. Gynecol. 174, 1354-1360. Polk, B.F. et al. (1989) Association of Chlamydia trachomatis and Mycoplasma hominis with intrauterine growth retardation and preterm delivery. Am. J. Epidemiol. 129, 1247-1257. Cotch, M.F. et al. (1987) Trichomonas vaginalis associated with low birth weight and preterm delivery. The Vaginal Infections and Prematurity Study Group. Sex. Transm. Dis. 24, 353-360. Romero, R. et al. (1989) Meta-analysis of the relationship between asymptomatic bacteriuria and preterm delivery/low birth weight. Obstet. Gynecol. 73, 576-582. McDonald, H.M. et al. (2007) Antibiotics for treating bacterial vaginosis in pregnancy. Cochrane Database Syst. Rev. 1, CD000262. Ison, C.A. and Hay P.E. (2002) Validation of a simplified grading of Gram-stained vaginal smears for use in genitourinary medicine clinics. Sex. Transm. Infect. 78, 413-415. McDonald, H.M. and Chambers H.M. (2000) Intrauterine infection and spontaneous midgestation abortion: Is the spectrum of microorganisms similar to preterm labour? Infect. Dis. Obstet. Gynecol. 8, 220-227. Annells, M.A. et al. (2005) Polymorphisms in immunoregulatory genes and the risk of histologic chorioamnionitis in Caucasoid women: a case control study. BMC Pregnancy Childbirth 5, 2. Xiong, X. et al. (2006) Periodontal diseases and adverse pregnancy outcomes: a systematic review. Brit. J.Obstet. Gynaecol. 113, 135-143. Vasquez, A. et al. (2002) Vaginal Lactobacillus flora of healthy Swedish women. J Clin Microbiol. 40, 2746-2749. Ferris, M.J. et al. (2007) Cultivation-independent analysis of changes in bacterial vaginosis flora following metronidazole treatment. J. Clin. Microbiol. 45, 1016-1018. Larsson, P.G. et al. (2008) Human lactobacilli as supplementation of clindamycin to patients with bacterial vaginosis reduce the recurrence rate: a 6-month, double-blind, randomized, placebo-controlled study. BMC Women’s Health 8, 3. Helen McDonald is an emeritus microbiologist, Women’s & Children’s Hospital, North Adelaide, where she was the chief medical scientist, Diagnostic Microbiology Laboratories, until her retirement in 2004. Prior to merger with the Adelaide Children’s Hospital she was the microbiologist in charge of the Queen Victoria Hospital Microbiology Laboratories (1976-1995), and during this time she gained her Gr.DipHA, FASM and PhD. Her major research interests are the role of vaginal flora/infection in PTB and neonatal sepsis, and vaginal microbicides for prevention of HIV acquisition. MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope Mother-to-child transmission of HIV: positive impacts of HIV from mother to child became the basis for studies on strategies for interrupting transmission 4. Pamela Palasanthiran Senior Staff Specialist and Conjoint Senior Lecturer, UNSW Department of Immunology and Infectious Diseases Sydney Children’s Hospital High Street, Randwick Tel (02) 9382 1508 Fax (02) 9382 1580 Email pamela.palasanthiran@ SESIAHS.health.nsw.gov.au Mother-to-child-transmission (MTCT) of HIV remains the major mode of paediatric HIV infection. Advances in the prevention of MTCT over the past decade and a half represent a major public health achievement. Strategies to prevent MTCT are now the standard of care for countries rich enough to afford the interventions. As such, perinatally acquired HIV in countries like the USA and Europe is now a rare event. With clearly documented declines in MTCT rates in resource rich countries, the focus is shifting towards any downsides of these strategies in pregnant women and for fetuses exposed in utero to antiretroviral (ARV) drugs and to infants postnatally. Cumulative evidence still supports the benefits of these strategies in preventing MCTC of HIV, with continued benefits for HIV pregnant women and their infants, and with minimal adverse outcomes. Knowledge of HIV infection status in pregnancy is critical for identifying the need for MTCT prevention. However, antenatal testing rates to identify HIV infected women is variable and an area that warrants attention. The overwhelming challenge in the 21st century is up scaling the availability of MTCT interventions in resource poor areas where more than 90% of the world’s HIV infected children now reside, and to develop optimal MTCT regimens that can be practically adopted in these settings. The milestones leading to the current successful MTCT intervention programmes has been a journey over more than 2 decades. The first was the recognition that the human immunodeficiency virus was not limited to transmission among the homosexual population but was also acquired via heterosexual contact, and transmissible from infected women to infants 1. The identification of risk factors associated with MTCT transmission, including the first report from Australia documenting the role of breast milk as a significant mode of HIV transmission 2,and more recently, the estimates of the timing of MTCT transmission3 have set the stage for studies on methods to interrupt transmission. The major risk factors associated with MTCT transmission viz. virus burden to which the child is exposed, duration of exposure and factors facilitating transfer M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 In 1994, the landmark trial on the use of the first licensed ARV, zidovudine (AZT), to prevent the transmission of HIV from mother to infants was halted early. Preliminary findings were so overwhelmingly in favour of its efficacy that continuing the study was unethical. PACTG 076 was a three part ARV approach to the interruption of HIV transmission from mother-to-child where pregnant women received AZT from 14 weeks of gestation, then intravenously during labour followed by 6 weeks of AZT to the infant. MTCT transmission was reduced by two thirds (from 22.6% to 8%) 3, 5. Since then, progress has been such that the three proven intervention strategies regarding ARV use to decrease maternal viral load antenatally and postnatal ARVs to infants – a component of which may be post-exposure prophylaxis, minimising duration of exposure to HIV by cesarean section before labour and before rupture of membrane and avoiding continued postnatal exposure to HIV by formula feeding infants – now achieves a phenomenally low rate of MTCT transmission. Historical MTCT rates of 20-30% are now in the order of 1-2% 6-9. The success of these measures in resource rich settings has been measurable and sustained. Perinatal HIV incidence in the USA has fallen by about 95% since 1992 10, similar to patterns in the UK and Ireland, and a selected Italian cohort 6-10. It appears that, overall, the benefits continue to outweigh potential risks 11. HIV does not adversely affect the clinical course of women 12. Combination therapy with highly active antiretroviral therapy (HAART) during pregnancy is efficacious, with the majority of women achieving viral suppression 13. Recent medium-term follow-up supports evidence for healthy maternal survival after use of ARVS during pregnancy, be it zidovudine monotherapy or HAART 14. Longer follow-up to 21 years in an Italian cohort is in further support of this 8. Concerns that ARVs are associated with prematurity has not been a consistent finding 15. Whilst concerns about mitochondrial toxicity in infants exposed to zidovudine in utero have been raised, evidence from large clinical trials do not support a significant risk of severe congenital anomalies, increase in malignancy or impaired growth and development in children exposed in utero to ARVs 16. However, strategies to prevent transmission can only be implemented if the diagnosis of HIV infection is known antenatally. Routine antenatal screening for HIV infection has long been a controversial issue, with those who argue against routine antenatal testing basing concerns on human rights issues, impact of false-positives results, the adequacy of counselling and appropriate post-test care of the woman 17. In Australia, paediatric HIV has always been rare. However, of concern is that children diagnosed with perinatal infection in the MTCT prevention era (post-1994) reflect missed opportunities for prevention strategies due to the lack of an antenatal diagnosis in pregnant HIV infected women. National surveillance data from 1994-2003 report a total of 206 perinatal exposures identified, 34 of 215 Under the Microscope which resulted in an HIV infected child. A disturbing proportion, 68% (23/34) of infants, were offspring of women whose HIV diagnosis was not made antenatally (Table 1). Cumulative data from 1982 – 2006 on the number of perinatally infected children in Australia show a substantial increase in mother-to-childtransmission rates if HIV infection is made postnatally compared to antenatally, reflecting the missed opportunities for prevention of MTCT (Figure 1). $YDLODELOLW\RI07&7 LQWHUYHQWLRQVVWUDWHJLHV 7LYJLU[HNL VM IPY[OZ @LHYVMIPY[O (U[LUH[HS/0=KPHNUVZPZ 7VZ[UH[HS/0=KPHNUVZPZ From Positive Pregnancy, a resource booklet for pregnant women living with HIV. Paediatric HIV Service, Sydney Children’s Hospital, Randwick, revised 2008. :V\YJL!(\Z[YHSPHU7HLKPH[YPJ:\Y]LPSSHUJL<UP[":[H[LHUK;LYYP[VY`OLHS[OH\[OVYP[PLZ Figure 1: Perinatal HIV infection in Australia (1982 – 2006), by year of birth and timing of mother’s HIV diagnosis. Acknowledgement: Ann McDonald, National Centre in HIV Epidemiology and Clinical Research (NCHECR). The Royal Australian and New Zealand College of Obstetricians (RANZCOG) recommend routine testing (a ‘universal testing’ approach) as part of antenatal care, whilst the 2006 National HIV testing policy recommends routine testing with essentially an ‘opt-out’ approach 18. The extent of antenatal HIV screening in Australia is not known but studies indicate that only 50-60% of obstetricians offer HIV tests antenatally 19, 20. The variable rate of antenatal HIV testing is also reflected in other centres in countries resourced to support testing 8, 21, 22. Overall, the public health challenge for the 21st century is up scaling access to workable MTCT prevention strategies in resource poor settings. Simple, successful interventions could mean preventing millions of HIV infected infants per year. The news is somewhat encouraging, for example access to ARVs for MTCT programmes appear to have increased in recent estimates, although progress is slow, and access to interventions still remains dismal in areas of greatest need (Figure2) 23. Recent focus on how to best to minimise transmission of HIV via breast milk by feeding practice and ARV regimens may provide part of a workable solution to impact on the current transmission rates in countries where infants are dependent on breast feeding for survival 24. In summary, the news is good for MTCT of HIV in rich countries where new cases of paediatric HIV are rare, and the downsides of these programmes minimal. An identified area of concern is the missed opportunities to prevent cases of HIV infected infants in these countries for lack of antenatal testing. Significant challenges exist for extension of the same success in preventing children from acquiring HIV in poorer countries. Figure 2: Percentage of pregnant women living with HIV and HIV exposed infants receiving antiretroviral prophylaxis for MTCT from seventy one middle and low income countries, 2004 - 2005 23. 12 10 8 11% 6 8% 7% 4 5% 2 0 HIV positive pregnant women receiving ARVs 2004 2005 HIV exposed infants receiving ARV Table 1. No. infected infants in Australia identified by timing of maternal HIV testing 1994-2003 18. Before birth: No. exposed No. with HIV At or after birth: No. exposed No. with HIV Total: No. exposed No. with HIV 1994-1995 24 7 20 8 44 15 1996-1997 16 3 10 7 26 10 1998-2001 46 0 7 5 54 5 2002-2003 38 1 1 0 39 1 160 11 45 23 206 34 Total 216 MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope References 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. Centers for Disease Control (1982) Unexplained immunodeficiency and opportunistic infections in infants: New York, New Jersey, California. MMWR Morb. Mortal Wkly. Rep. 31, 665-667. Ziegler, J.B. et al. (1985) Postnatal transmission of AIDS-associated retrovirus from mother to infant. Lancet 1, 896-898. Kourtis, A.P. et al. (2006) Mother-to-child transmission of HIV-1: timing and implications for prevention. Lancet Infect. Dis. 6, 726-732. McIntyre, J. (2006) Strategies to prevent mother-to-child transmission of HIV. Curr. Opin. Infect. Dis. 19, 33-38. Connor, E.M. and Sperling, R.S. (1994) Reduction of maternal-infant transmission of human immunodeficiency virus type 1 with zidovudine (AZT) treatment. N. Engl. J. Med. 331, 1173-1180. European Collaborative Study (2005) Mother-to-child transmission of HIV infection in the era of highly active antiretroviral therapy. Clin. Infect. Dis. 40, 458-465. European Collaborative Study (2006) The mother-to-child HIV transmission epidemic in Europe: evolving in the East and established in the West. AIDS 20, 1419-1427. Martinelli, P. et al. (2008) Epidemiological and clinical features of pregnant women with HIV: a 21-year perspective from a highly specialized regional center in southern Italy. HIV Clin. Trials 9, 36-42. Townsend, C.L. et al. (2008) Low rates of mother-to-child transmission of HIV following effective pregnancy interventions in the United Kingdom and Ireland, 2000-2006. AIDS 22, 973-981. Centers for Disease Control and Prevention (2006) Achievements in public health. Reduction in perinatal transmission of HIV infection: United States, 1985-2005. MMWR Morb. Mortal Wkly. Rep. 55, 592-597. Thorne, C. and Newell, M.L. (2007) Safety of agents used to prevent mother-to-child transmission of HIV: is there any cause for concern? Drug Saf. 30, 203-213. Gray, G.E. and McIntyre, J.A. (2007) HIV and pregnancy. BMJ 334, 950-953. Watts, D.H. et al. (2003) Progression of HIV disease among women following delivery. J. Acquir. Immune Defic. Syndr. 33, 585-593. 14. Martin, F. et al. (200 6) Pregnant women with HIV infection can expect healthy survival: three-year follow-up. J. Acquir. Immune Defic. Syndr. 43, 186-192. 15. Kourtis, A.P. et al. (2007) Use of antiretroviral therapy in pregnant HIV-infected women and the risk of premature delivery: a meta-analysis. AIDS 21, 607-615. 16. Townsend, C.L. et al. (2006) Antiretroviral therapy and congenital abnormalities in infants born to HIV-1-infected women in the United Kingdom and Ireland, 1990 to 2003. J. Acquir. Immune Defic. Syndr. 42, 91-94. 17. Lo, B. et al. (2000) Ethical issues in early detection of HIV infection to reduce vertical transmission. J. Acquir. Immune Defic. Syndr. S136-S143. 18. National HIV Testing Policy. (2006) http://www.health.sa.gov.au/PEHS/PDF-files/hivtesting-policy-2006.pdf 19. Giles, M.L. et al. (2004) An audit of obstetricians’ management of women potentially infected with blood-borne viruses. Med. J. Aust. 180, 328-332. 20. Giles, M.L. et al. (2006) The evidence for a change in antenatal HIV screening policy in Australia. Med. J. Aust. 185, 217-220. 21. Gruslin, A. et al. (2001) Prenatal HIV screening in a tertiary care centre. Can. J. Public Health 92, 255-258. 22. Simpson, W.M. et al. (1999) Antenatal HIV testing: assessment of a routine voluntary approach. BMJ 318, 1660-1661. 23. Interagency Task Team. (2007) Guidance on global scale up of the prevention of mother to child transmission of HIV. http://www.unicef.org/aids/files/PMTCT_ enWEBNov26.pdf 24. Read, J.S. (2008) Prevention of mother-to-child transmission of HIV through breast milk. Pediatr. Infect. Dis. J. 27, 649-650. Dr Pamela Palasanthiran (MBBS, MD, FRACP) is a practising staff specialist in paediatric infectious diseases and a conjoint lecturer at the University of New South Wales. Her major interests include perinatal infections and she specialises in paediatric HIV. Intrauterine infection: preterm birth and pulmonary impact Monica M Lahra Senior Lecturer Department of Immunology and Infectious Diseases, Faculty of Medicine, University of Sydney, NSW Email [email protected] … chorioamnionitis is a condition that cannot be diagnosed accurately until after the event, its cause appears multifactorial and non-specific, and treatment cannot be designed until after the cause is found – and then it is too late. Where are we going wrong? There is a long road ahead that must be taken because, in a time of low perinatal morbidity and mortality, the disorder is rapidly assuming an important role, if only by default. No longer is chorioamnionitis merely an interesting finding for pathologists to demonstrate to their colleagues 1. This is an excerpt from a letter published anonymously in the Lancet in 1989. Acute chorioamnionitis is the histological hallmark of intrauterine infection and remains today the focus of intense, and increasing, research interest. This interest is underpinned by the association of chorioamnionitis with preterm delivery. Extreme prematurity is the fundamental, unresolved problem in perinatal medicine, has associated high morbidity and mortality, and accounts for a significant proportion of the M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 health expenditure in the developed world 2. The preterm delivery rate is increasing in Australia, from 6.8% in 1991 to 8.1% in 2005 1. Advancement in intensive care practice has increased survival of very preterm neonates, and this has meant an increase in diseases that are directly related to prematurity, such as cerebral palsy and neonatal chronic lung disease (CLD). Epidemiology Histological studies of the placentae of live-born infants consistently report chorioamnionitis to be most common in preterm populations, with the highest rates in the lowest gestational age groups, and the predominance in pregnancies less than 32 weeks’ gestation. A recent Australian study of 3928 preterm infants between 20 -34 weeks’ gestation demonstrated the clear inverse relationship between histological chorioamnionitis and gestation, with the incidence of chorioamnionitis in those born at 20-24 weeks 66%, decreasing to 16% at 34 weeks 2. Pathogenesis of intrauterine infection There are four potential pathways for intrauterine infection. The first and most common route is ascending infection from the lower genital tract. Infrequently, infection can occur via retrograde passage of organisms from the peritoneal cavity via the fallopian tubes, haematogenously from the maternal circulation and from invasive antenatal diagnostic procedures, such as amniocentesis 2. Ascending intrauterine infection After overgrowth in the vagina and cervix, organisms gain access to the space between the amniotic membranes and the uterus to cause localised inflammation, and this can cause rupture of the membranes. Further extension of infection may 217 Under the Microscope follow, and/or the organisms can cross the amniotic membranes (intact or ruptured) to infect the amniotic fluid. Membrane rupture can also occur at this point, when there is infection and inflammation on both sides of the membranes 2. Histologically this initial inflammatory response to ascending infection is seen as infiltration of predominantly maternal polymorphonuclear leucocytes (PMNLs) into the membranes (chorion and amnion). This is termed chorioamnionitis. A fetal inflammatory response occurs in response to exposure of the umbilical cord to infected amniotic fluid. The infecting bacteria and bacterial products in the amniotic fluid activate the fetal white cells in the blood vessels in the umbilical cord. This results in PMNLs migrating from the intravascular space of the umbilical vessels into the vessel walls, and potentially beyond the vessel walls to the cord stroma. This fetal inflammatory response to infected amniotic fluid can occur without fetal infection and contributes to labour onset and delivery. Less commonly, fetal infection may occur via by aspiration or ingestion of infected amniotic fluid. Alternatively, skin or mucous membrane infection can occur in the fetus after contact with infected amniotic fluid, with the potential for the development of fetal systemic infection. It is also possible for fetal infection to occur via spread from the decidual layers to the intervillous space 2. Thus the inflammatory responses to ascending intrauterine infection are of both maternal and fetal origin and occur as part of a continuum, with the initial inflammatory response of maternal origin and a fetal inflammatory response subsequent. This explains the relationship of preterm rupture of membranes (PROM) with intrauterine infection. Evidence supports the relationship of intrauterine infection as a likely cause and not an effect of prematurity and PROM. This hypothesis, based on an understanding of pathogenesis, is a departure from the earlier and largely discarded supposition that chorioamnionitis is a complication of both preterm labour and PROM. Microbiology The microbiological findings are discussed in this issue by Dr Helen McDonald. Diagnosis The clinical hallmarks of chorioamnionitis include uterine tenderness, tachycardia, fever and a raised maternal white cell count. However, in the majority chorioamnionitis is asymptomatic until labour onset or rupture of membranes. In the current clinical setting, histological examination of the placenta, extraplacental membranes and umbilical cord is often the mainstay of diagnosis. Clinical implications Intrauterine infection is known to be associated with the onset of preterm labour and delivery and with a decreased incidence of neonatal respiratory distress syndrome (RDS). RDS occurs in preterm infants because of structural and functional lung immaturity. RDS occurs in 60-80% infants born at <28 weeks’ gestation, and 10-15% of infants 32-36 weeks’ gestation at delivery 2. Treatment for RDS includes mechanical ventilation which can result in lung injury from a combination 218 of barotrauma and oxygen toxicity. This lung injury predisposes the infant to CLD. Further, there is a reported association of intrauterine infection and CLD which is controversial and discussed briefly below. Intrauterine infection is also reported to be associated with sepsis in the newborn, as are adverse neurological outcomes which will not be discussed here. Intrauterine infection and preterm labour Intrauterine bacterial invasion triggers preterm labour via a number of interacting pathways 2. The bacterial endo and exotoxins stimulate the uterine lining (decidua) and fetal membranes to produce a range of proinflammatory cytokines including tumour necrosis factor (alpha), interleukin-1, interleukin-6, interleukin-8 and granulocyte colony stimulating factor. Both the bacterial products and the proinflammatory cytokines induce prostaglandin production by the chorioamnion, placenta and decidua, and recruit and activate PMNLs. These activated PMNLs synthesise and release a range of bioactive products including collagenases and elastases that degrade connective tissue 3. The combined effect of prostaglandins and collaganase and elastase play a key role in initiation of both labour at term 4, and preterm labour and delivery 2 via a similar final common pathway. Increased prostaglandin concentration stimulates uterine contractions and the collagenases and elastases weaken the chorioamnionitic membranes and remodel and soften the cervical collagen 2, 3. It is thought that spontaneous term labour is initiated via the fetal hypothalamic-pituitary-adrenal axis (HPA) 4. Studies in humans indicate that the fetal HPA axis is activated by intrauterine infection 4. The HPA axis is part of the peripheral stress system. Interleukin-1, interleukin-6 and tumour necrosis factor (alpha) independently and, in combination synergistically, activate the HPA axis during the stress of inflammation. The end products of HPA activation are glucocorticoids which inhibit the production and effect of inflammatory cytokines 5 . Glucocorticoids also accelerate maturation of the fetal lung physiologically, morphologically and biochemically 6. This is the biological rationale for both the reduction of RDS in the presence of intrauterine inflammation, and therapeutic maternal antenatal steroid administration in preterm labour. Intrauterine infection and pulmonary implications In 1969 Liggins demonstrated that glucocorticoids decreased RDS and enhanced survival in preterm lambs 3. Studies have shown that the presence of chorioamnionitis is associated with a significant decrease in the incidence of RDS. A very recent study of preterm newborns investigated the impact of fetal versus maternal inflammatory responses on the incidence of RDS. A greater reduction in odds for RDS with found with a fetal inflammatory response (adjusted OR 0.23, 95% CI 0.15-0.35) than with a maternal inflammatory response (chorioamnionitis) (adjusted OR 0.49, 95% CI 0.31-0.78) 4. This indicates a dose response relationship between the degree of inflammatory response and reduction in RDS 4. Early studies showed chorioamnionitis to be associated with CLD; however, recent studies in the current clinical context have MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 Under the Microscope shown no relationship or a protective effect 3-6. The postulation that intrauterine infection reduces RDS but increases CLD is difficult to reconcile biologically, as RDS and its treatment, and mechanical ventilation and oxygen therapy independently, are on the causal pathway for CLD 6. Intrauterine infection, neonatal sepsis and CLD An immature immune system predisposes the preterm infant to infection. Neonatal sepsis is defined as early or late onset. This is because infection occurring early after delivery is often associated with transmission from the mother (vertical transmission), whereas late onset neonatal sepsis is generally nosocomially acquired. Australian multi-centre data show the incidence of late onset sepsis in infants <1000 grams to be 22.6%, and decreasing with increasing gestation 7. There is conflicting evidence regarding the association of intrauterine infection and neonatal sepsis, regardless of onset. However, neonatal sepsis has been shown to be an independent risk factor for CLD. This has significant implications given that the majority of neonatal sepsis is nosocomially acquired. Future research Many questions remain regarding intrauterine infection and its impact on the fetus and neonate. What is clear is that the most crucial relate to primary prevention of this disease, and to the improvement in infection control in the newborn intensive care. References 1. National Perinatal Statistics Unit, AIHWA Australia’s Mothers and Babies (2005) http://www.npsu.unsw.edu.au/NPSUweb.nsf/page/ps20. 2. Goldenberg, R.L. et al. (2000) Intrauterine infection and preterm delivery. New Eng. J. Med. 342, 1500-1507. 3. Andrews, W.W. et al. (2006) The Alabama preterm birth study: polymorphonuclear and mononuclear cell placental infiltrations, other markers of inflammation, and outcomes in 23- to 32-week preterm newborn infants. Am. J. Obstet. Gynecol. 195, 803-808. 4. Kent, A. and Dahlstrom, J.E. (2004) Chorioamnionitis/funisitis and the development of bronchopulmonary dysplasia. J. Paediatr. Child Health 40, 356-359. 5. Redline, R.W. et al. (2002) Placental and other perinatal risk factors for chronic lung disease in very low birth weight infants. Pediatr. Res. 52, 713-719. 6. Lahra, M. et al. (2008) Intrauterine inflammation, neonatal sepsis and chronic lung disease: a 13 year hospital cohort study. Pediatr. In press. 7. Isaacs, D. et al. (1996) Late-onset infections of infants in neonatal units. J. Paediatr. Child Health 32, 158-161. Monica Lahra (BA, MBBS, Dip Paed, FRCPA, MASM) is a medical microbiologist trained at the Prince of Wales Hospital in Sydney. Her recently submitted PhD thesis focused on the impact of intrauterine infection on the fetus and neonate. Her research interests include perinatal infection and infection in childhood. She has co-authored the chapter The impact of infection in pregnancy in the 4th edition of Fetal and Neonatal Pathology by JW Keeling and T Yee Khong (Eds). Call for Nominations – President-Elect Associate Professor Keryn Christensen’s term as Immediate Past President concludes at the Annual General Meeting which will be held in July 2009. In accordance with the ASM Constitution, nominations are invited for the position of President-Elect of the Society, to take office in July 2009 following the Annual General Meeting. The President-Elect will hold office until the next Annual General Meeting, to be held in July 2010, at the conclusion of which he or she will become President. Candidates for election to the position of President-Elect shall be Honorary Life Members, Financial Fellows, Members or Senior Associate Members of the ASM and be proposed and seconded by Honorary Life Members, Financial Fellows, Members or Senior Associate Members of the Society. Nominations must have the written consent of the candidate. Nominations must be received by the ASM National Office Manager before 5pm Wednesday 31 December 2008. Please use the nomination for the position of President-Elect form, which is set out opposite. M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 Nomination for the position of President-Elect of the Australian Society for Microbiology Inc We the undersigned wish to nominate: __________________________________________________________________ of: _______________________________________________________________ for the position of President-Elect of the Australian Society for Microbiology Inc. Proposer (FASM / MASM / SASM / Honorary Life Member) Name: ___________________________________________________________ Signature: ________________________________________________________ Seconder (FASM / MASM / SASM / Honorary Life Member) Name: ___________________________________________________________ Signature: ________________________________________________________ I accept this nomination for the position of President-Elect of the Australian Society for Microbiology Inc. Name: ___________________________________________________________ Signature: ________________________________________________________ Date: ________________________________ Address your envelope as follows: National Office Manager, Australian Society for Microbiology Inc Suite 23, 20 Commercial Road, Melbourne VIC 3004 Alternatively you may fax your nomination form to the National Office on (03) 9867 8722 219 ASM Affairs National Scientific Advisory Committee (NSAC) Divisional Chairs 2011 Call for expressions of interest Expressions of interest are requested for the following positions on the National Scientific Advisory Committee (NSAC). • Provide input and advice to the organisers of the 2010 Annual • Division 1 Chair (2011) Medical and Veterinary Microbiology • Provide scientific advice to the society as a member of NSAC. • Division 2 Chair (2011) Virology • Division 3 Chair (2011) General, Applied and Environmental Microbiology Scientific Meeting. It is envisaged that the divisional representatives will be researchers and scientists with enthusiasm, good organisational and communication skills, and broad knowledge and an excellent or developing reputation in the divisional field. • Division 4 Chair (2011) Microbial Genetics, Physiology and Pathogenesis Fellows, Members, Senior Associate or Associate Members The successful appointees will have the opportunity to serve a 3 year term of office, concluding at the end of the 2011 Annual Scientific Meeting, which will be held in Hobart. honorary positions should submit a brief curriculum vitae (no The primary responsibilities of the Division Chairs will be to: Associate Professor Liz Harry (Vice-President, Scientific Affairs) • Organise the symposium component of the 2011 Annual Scientific Meeting. by email to the National Office [email protected] interested in serving in these exciting and challenging new more than two pages), together with an appropriate covering letter to: by 21 December 2008. ASM Distinguished Service Award The Distinguished Service Award recognises outstanding service of, or contributions by, individuals or organisations to the Society. Procedure for nomination Individual ASM Members or Fellows, Committees or Branches may nominate individual ASM members or organisations for a Distinguished Service Award. Nominations should be sent to the National Office Manager, Michelle Jackson (michelle@ theasm.com.au). A person or organisation shall not be considered for a Distinguished Service Award unless the National Office has received from the proposers: • a nomination for Distinguished Service Award signed by the proposer and a seconder, each of whom shall be a Member or Fellow of the Society; and Assessment and award The Executive Committee will review the nominations received and place those considered acceptable and of sufficient merit in priority order. The Executive Committee will present a summary report on nominations received and the names of up to 10 recommended awardees to National Council. No more than 10 Distinguished Service Awards shall be awarded in any one year. Distinguished Service Awards will be announced at the next Annual General Meeting and the ASM National Conference. Closing date for nominations: 30 November of any year. Acknowledgement: An acknowledgement will be emailed within 5 business days of receiving your application. If this has not been received, please contact Michelle Jackson at the ASM National Office on (03) 9867 8699. • a statement summarising the nominee’s major contribution to the Society. 220 MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 ASM Affairs New ASM Life Member, Ruth Bishop AO Ruth Bishop is a graduate in microbiology from the University of Melbourne. Her long-term research career, based at the Department of Gastroenterology at the Royal Children’s Hospital Melbourne, and later at the Murdoch Children’s Research Institute, Melbourne, focused initially on qualitative and quantitative studies of gut flora, in particular of the small intestine in children with a variety of malabsorptive diseases including coeliac disease, cystic fibrosis, sugar malabsorption and short-gut syndrome. In 1971 she combined with paediatricians Rudge Townley and Graeme Barnes in research aimed at understanding the pathophysiology of severe acute gastroenteritis in young children. This research showed that the duodenum of these children was acutely inflamed, indicating the presence of an ‘unknown’ infectious agent. In 1973 she led a team, including paediatrician Geoff Davidson, electron microscopist Brian Ruck and virologist Ian Holmes, that discovered a ‘new’ virus (now called rotavirus) in duodenal tissue and faeces from children admitted to hospital with severe dehydrating gastroenteritis. Ruth has subsequently pursued the goal of preventing this serious infection that still kills more than half a million children each year worldwide. Careful immunological, epidemiological and virological studies within Australia, and globally via her role in chairing several WHO Committees and as Director of a WHO Collaborating Laboratory, have influenced international development of rotavirus vaccines. It is a tremendous local outcome of the worldwide program that oral rotavirus vaccines were introduced into the routine immunisation schedule for all Australian children from July 2007. The Group continues to develop a cheap, affordable Australian candidate rotavirus vaccine aimed at use in developing countries. Ruth has been the recipient of many awards including the University of Melbourne Selwyn-Smith Prize for Clinical Research (1978), The Clunies Ross National Science and Technology Award (1998), The Children’s Vaccine Initiative Award (Geneva, 1998) Royal Children’s Hospital Gold Medal (1994), and Honorary Fellowship of the Royal Australasian College of Physicians (2008). Ruth was made a Life Member of the Australian Society for Microbiology in July 2008. Ruth Bishop AO, DSc, PhD Senior Principal Research Fellow Murdoch Children’s Research Institute Royal Children’s Hospital, Flemington Rd, Parkville VIC 3052 Tel (03) 9345 5062 Fax (03) 9345 6240 Email [email protected] Obituaries Graeme Laver ASM member Dr Graeme Laver has died in London at the age of 79. Graeme’s research on the influenza virus spanned a period of more than 30 years. His work at the John Curtin School of Medical Research, ANU, helped develop the anti-flu drug Relenza. In 1996, Graeme was awarded the Australia Prize for excellence in the field of pharmaceutical design. Graeme was very much a public figure and his lectures at ASM meetings often attracted media attention. His last contribution to Microbiology Australia was in the special influenza (November 2006) issue. This contribution was another interesting perspective on the origins of pandemic influenza. Milton RJ Salton, FRS Milton Salton received his BAgSci degree in 1945 from the University of Sydney. In 1948, Salton was awarded a CSIRO fellowship for postgraduate study at Cambridge, receiving a PhD in 1951 and subsequently a ScD. At Cambridge he began his pioneering studies that led to the discovery of the bacterial cell wall. He continued these investigations during postdoctoral studies at the University of California. In 1956, Salton was appointed as a Reader of Chemical Bacteriology at the University of Manchester. In 1961 he returned to the University of New M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 South Wales as the Foundation Professor of Microbiology. In 1964, he was recruited by Severo Ochoa, NL to head the Microbiology Department at New York University School of Medicine. He remained there for over 25 years as Professor and Chairman until his retirement in 1991. Many of Salton’s seminal papers on the bacterial cell wall were published in the 1950s and early 1960s. In a paper published in Nature in 1952, Salton showed that the cell wall is the substrate for lysozyme action in Micrococcus lysodeicticus, and between 1951 and 1961 he published a series of eight papers with the common title Studies of the bacterial cell wall. These and other publications helped to explain why bacteria either do or don’t take up the Gram stain and also laid the basis for the understanding of the mechanism of action of penicillin on bacterial cell wall synthesis. His later work at NYU focused on both the physical and biochemical elucidation of the unique macromolecular structure of the bacterial cell wall and the multiple functions it served. The above was extracted from an article written by Joel D Oppenheim and Jan Vilcek (New York University School of Medicine, New York), and published in the American Society for Microbiology’s Microbe Magazine. 221 ASM Affairs IUMS 2008 Microbiologists met where East meets West – Istanbul, Turkey biotechnology and biobusiness symposium. Invited speakers Dr Stuart Cordwell (University of Sydney) and Dr Wieland Meyer (Westmead Hospital, Sydney) talked on the Comparative surface proteomics and glycoproteomics of virulent Campylobacter jejuni and MLST typing in Crytococcus neoformans species respectively. At the virology congress, fascinating developments in viral genomes and bioinformatics as well as emerging viral pathogens were covered; Dr TuckWeng was the representative from Australia. Bosphorus Bridge View of Golden-Horn from the Congress Centre. Meetings of the three divisions of the International Union of Microbiological Societies (IUMS) – hosted by the Turkish Microbiological Society, the Society for Microbial Ecology and the Society of Chemotherapy – took place in Istanbul, Turkey in August. The meeting started with the XII International Congress of Bacteriology and Applied Microbiology and the XII International Congress of Mycology (5-9 August 2008) and was followed by the XIV International Congress of Virology (10-15 August 2008). Prof. Michael Hecker (Germany), Prof. Mariana Viviani (Italy) and Prof. Robert Lamb (USA) chaired the programmes for the bacteriology, mycology and virology divisions respectively. Australia was represented in the international advisory boards for all of the three divisions of the IUMS. Current IUMS President Prof. Karl-Heinz Schleifer (Germany) and Chairman of the Turkish National Organising Committee Prof. Özdem Ang welcomed the participants at the opening ceremony while the screen was filled with beautiful views of Istanbul and Turkish folk dancers performed on the stage. Australia was represented in significant numbers of participants chairing symposia or delivering oral and poster presentations. Prof. Hatch Stokes represented the ASM and Prof. David Ellis attended the Mycology Division Committee meetings which took place throughout the conference. Current Chair of the IUMS mycology division Prof. Graham Fleet (UNSW) chaired the Food mycology symposium and Prof. Barbara Howlett (University of Melbourne) gave the keynote lecture on Mechanisms of fungal pathogenesis in plants and animals. The symposium Interactions in the microbial world was chaired by Prof. Steffan Kjelleberg (UNSW), and Dr Ipek Kurtböke (USC) chaired the Actinobacteria: an unexhausted source for biodiscovery, 222 All three Congresses captured recent advances ranging from metabolic engineering, functional genomics/pathogenomics, physiological proteomics, and systems microbiology to biotechnology and applied microbiology expanding towards bioenergy. They also covered the evolving global landscape to biosafety and pathogen security practices as well as the emerging pathogens. Other highlights included Antibiotics and pathogenicity, chaired by Prof. Julian Davies (Canada) and Bergey plenary session: taxonomy of prokaryotes, chaired by Prof. James Staley (USA) and Prof. Karl-Heinz Schleifer (Germany). In the symposium organised by the World Federation of Culture Collections, Facing the transition from culture collections to biological resource centre was discussed. Current international progress included in that symposium again provided impetus for us to provide support towards formal recognition of the Australian Microbial Resources Research Network. On a personal note, I was delighted to greet my Australian colleagues in beautiful Istanbul where I grew up. Full details of the Congress programme and names of the Australian participants can be viewed at http://www.iums2008. org/. The next IUMS will be in Sapporo, Japan in 2011. Ipek Kurtböke University of the Sunshine Coast, QLD Ipek Kurtböke, David Ellis & Hatch Stokes sailing on the Bosphorus at the congress dinner. Prof. J Martin and Prof. P Liras of Spain with Ipek Kurtböke at the Actinobacteria symposium. MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008 What’s On 2008-2010 meetings Contributions listing relevant meetings are welcome. Please send to: [email protected] 2008 12 November 2008 Food Science Australia, Brisbane QLD Food Microbiology Seminar Series: Tales from the Green Book Gary Grohman (Enviro Path) on Ch.22 – Viruses Sofroni Eglezos, Series Coordinator & ASM Food Micro SIG Tel (07) 3848 3622 Email [email protected] 4-7 December 2008 Foshan, China 2nd Annual World Congress of Gene-2008 (WCG 2008): Decoding Life for Human Health The tradition of the conference dates back to 3 years ago in Dalian, China, which brought together five Noble Prize Laureates and more than 3000 participants to celebrate the discovery of the double helix. www.bitlifesciences.com/wcg2008 2009 – Golden Jubilee Year 22-25 February 2009 Baltimore, MD, USA 7th ASM Biodefense and Emerging Diseases Research Meeting 25-28 March 2009 Cypress Lakes Resort, Hunter Valley NSW ASID 2009 – Australasian Society for Infectious Diseases (ASID) Annual Scientific Meeting 10-13 May 2009 Buenos Aires, Argentina VTEC 2009 – 7th International Symposium on Shiga Toxin (Verocytotoxin) – Producing Escherichia coli Infections www.vtec2009.com.ar 17-21 May 2009 Philadelphia, PA, USA 109th General Meeting of American Society for Microbiology www.asm.org 21-25 June 2009 Hamilton Island QLD Australia 10th International Symposium on Double-Stranded RNA Viruses Coordinators: Barbara Coulson & John Taylor www.dsrna2009.org 28 June – 2 July 2009 Goteborg, Sweden FEMS 2009 – Third Congress of European Microbiologists: Microbes and Man – Interdependence and Future Challenges www2.kenes.com/fems-microbiology/Pages/home.aspx 6-10 July 2009 Perth Convention Centre, Perth WA ASM 2009 Perth – Annual Scientific Meeting & Exhibition Australia’s largest microbiology event for 2009 celebrating ASM’s 50th Golden Jubilee Year. Chair, Local Organising Committee: Rod Bowman Chair, Scientific Programme Committee: Harry Sakellaris Conference Management: Australian Society for Microbiology Contact: Janette Sofronidis, Conference Manager www.asid.net.au 30 March – 2 April 2009 Harrogate International Centre, UK SGM 164th Meeting 7-9 May 2009 The Carrington Hotel, Katoomba, Blue Mountains, NSW Viruses in May Australia’s only meeting focused specifically on the clinical, diagnostic & management aspects of viral infections. Programme themes: • Principles of clinical virology • Congenital infection • Paediatric infection & vaccination • Blood borne viruses • Hepatitis Convenors: Professor Bill Rawlinson & Dr Monica Lahra Conference Management: Australian Society for Microbiology Contact: Meg Lukies, Event Coordinator www.virusesinmay.com M I CROB I O L O G Y A U S T RALIA • NOVE MB E R 2 0 0 8 29-31 October 2009 Hamilton Island, QLD Mycology MasterClass IV [1 November 2009 – Additional MasterClass Workshop for laboratory staff] Convenor: Associate Professor David Ellis Conference Management: Australian Society for Microbiology Contact: Janette Sofronidis, Conference Manager 2010 28 June – 1 July 2010 Melbourne Convention and Exhibition Centre, Melbourne VIC 11th International Symposium on the Genetics of Industrial Microorganisms Chair: Ian Macreadie www.gim2010.org 4-8 July 2010 Darling Harbour Convention Centre, Sydney NSW ASM 2010 Sydney 223 Who’s Who Australian Society for Microbiology Incorporated NATIONAL COUNCIL EXECUTIVE President Prof Hatch Stokes Past President Assoc Prof Keryn Christiansen Vice-President, Scientific Affairs Assoc Prof Liz Harry Vice-President, Corporate Affairs Dr Johnson Mak BRANCH DELEGATES ACT/ Ian Carter NSW QLD Dr Sandra Hall SA Stephen Davies TAS Dr Louise Roddam VIC Sue Cornish WA Suellen Blackaby NT (sub branch) Mr Kevin Freeman Chair, National Scientific Advisory Committee Assoc Prof Liz Harry Chair, National Examinations Board Prof Peter Coloe Chair, National Qualifications Committee Dr Ruth Foxwell Convenor, Visiting Speakers Program Dr Mary Barton Editor, Microbiology Australia Prof Ian Macreadie/Mrs Jo Macreadie Registrar, National Examinations Board Assoc Prof Margaret Deighton Public Officer of the Society Dr Ruth Foxwell Executive Officer Dr Carol Ginns National Office Manager Michelle Jackson Conference Manager Janette Sofronidis Event Coordinator & Registration Services Meg Lukies Membership Services Lina Raco BRANCH SECRETARIES ACT/NSW Kerry Varettas Senior Hospital Scientist SEALS Microbiology St George Hospital Gray Street, Kogarah NSW 2217 Tel (02) 9350 3325 Fax (02) 9350 3349 Email [email protected]. nsw.gov.au QLD Dr Patrick Blackall Animal Research Institute Locked Mail Bag 4 Moorooka QLD 4105 Tel (07) 3362 9498 Email [email protected] SA Stephen Davies Women’s & Children’s Hospital Mycology Section 72 King William Road North Adelaide Tel (08) 8161 7365 Email [email protected] TAS Ms Sarah Foster LGH, Cnr Franklin and Charles Streets Launceston TAS 7250 Tel (03) 6348 7670 Email [email protected] VIC Ms Sue Cornish Mayfield Education Centre 2-10 Camberwell Road Hawthorn East VIC 3123 Tel (03) 9811 9012 Email [email protected] 224 WA Miss Nicola Barrett PathWest Microbiology and Infectious Diseases QE2 Medical Centre, SCGH Hospital Avenue, Nedlands WA 6009 Tel (08) 9224 2444 Email [email protected] NT (sub branch) Mr Paul Southwell Royal Darwin Hospital Microbiology TIWI NT 8100 Tel (08) 8922 8004 Email [email protected] CONVENORS OF ASM STANDING COMMITTEES ASM Foundation Dr Ray Akhurst CSIRO, Division of Entomology GPO Box 1700, Canberra ACT 2601 Tel (02) 6246 4123 Email [email protected] BioSafety Mr Lee Smythe, Supervising Scientist WHO/FAO/OIE Collaborating Centre for Reference & Research on Leptospirosis Queensland Health Scientific Services 39 Kessels Rd, Coopers Plains QLD 4108 Tel (07) 3274 9064 Fax (07) 3274 9175 Email [email protected] Clinical Microbiology Dr Stephen Graves Director of Microbiology Hunter Area Pathology Service (HAPS) John Hunter Hosp, Newcastle NSW 2300 Tel (02) 4921 4420 Mobile 0407 506 380 Fax (02) 4921 4440 Email [email protected]. gov.au Ethics Committee Emeritus Prof Nancy Millis University of Melbourne School of Microbiology, Parkville VIC 3052 Tel (03) 9344 5707 Email [email protected] National Scientific Advisory Committee Assoc Prof Liz Harry University of Technology Sydney Inst. for Biotech. of Infect. Diseases Broadway NSW 2007 Tel (02) 9514 4173 Fax (02) 9514 4021 Email [email protected] Publications/Editorial Board Dr Ailsa Hocking CSIRO, Div Food Science & Technology PO Box 52, North Ryde NSW 2113 Tel (02) 9490 8520 Email [email protected] Research Trust Advisory & Development Committee Assoc Prof Elizabeth Dax National Serology Reference Laboratory 4 Fl, Healy Building 41 Victoria Parade, Fitzroy VIC 3065 Tel (03) 9418 1111 Email [email protected] convenors of asm special interest groups Division 1 Antimicrobials Dr John Merlino Concord Repatriation General Hospital Microbiology and Infectious Diseases Hospital Road, Concord NSW 2173 Tel (02) 9767 6658 Email [email protected] Mycobacteria Dr Janet Fyfe Mycobacterium Reference Laboratory Victorian Infectious Diseases Reference Laboratory, 10 Wreckyn Street North Melbourne VIC 3051 Tel (03) 9342 2617 Fax (03) 9342 2666 Email [email protected] Mycology Dr Weiland Meyer, Westmead Hospital ICPMR CIDMLS Microbiology Level 2, Room 3114A Darcy Road, Westmead NSW 2145 Tel (02) 8344 5701 Email [email protected] Mycoplasmatales Dr Steven Djordjevic Elizabeth Macarthur Agricultural Institute Private Mail Bag 8, Camden NSW 2570 Tel (02) 4640 6426 Email [email protected] Ocular Microbiology Dr Carol Lakkis University of Melbourne Clinical Vision Research Aust Crn Cardigan & Keppel St Carlton VIC 3053 Tel (03) 9349 7420 Fax (03) 9349 7498 Email [email protected] Parasitology & Tropical Medicine Dr Andrew Butcher Senior Medical Scientist Adjunct Senior Lecturer University of South Australia Institute of Medical & Veterinary Science The Queen Elizabeth Hospital Department of Clinical Microbiology & Infectious Diseases 28 Woodville Road, Woodville SA 5011 Tel (08) 8222 6728 Fax (08) 8222 6032 Email [email protected] Public Health Microbiology Dr Geoffrey Hogg University of Melbourne Microbiological Diagnostic Unit Parkville VIC 3052 Tel (03) 8344 5713 Email [email protected] Clinical Serology & Molecular David Dickeson Serology Manager, Centre for Infectious Diseases & Microbiology Lab Services Level 3, ICPMR, Westmead Hospital Westmead NSW 2145 Tel (02) 9845 6861 Fax (02) 9633 5314 Email [email protected]. nsw.gov.au Veterinary Microbiology Dr Glenn Browning The University of Melbourne Vet Preclinic Centre Gratton Street, Parkville VIC 3052 Tel (03) 8344 7342 Email [email protected] Women’s & Children’s Microbiology Convenor Dr Suzanne Garland Royal Children’s Hospital Microbiology, 132 Grattan Street Melbourne VIC 3000 Tel (03) 9344 2476 Email [email protected] Secretary Mr Andrew Lawrence Women’s & Children’s Hospital Microbiology & Infectious Diseases Dept 72 King William Rd, Nth Adelaide SA 5006 Tel (08) 8161 6376 Fax (08) 8161 6051 Email [email protected] Division 2 Virology Vacant Division 3 AquaSIG – Water Microbiology Mr Simon Rockliff ACT Health ACT Government Analytical Laboratories Micro Section, Locked Bag 5, Western Creek ACT 2611 Tel (02) 6205 8701 Fax (02) 6205 8703 Email [email protected] Cosmetics & Pharmaceuticals Dr Paul Priscott AMS Laboratories Pty Ltd 8 Rachael Close Silverwater NSW 2128 Tel (02) 9704 2300 Mobile 0414 772 096 Fax (02) 9737 9425 Email [email protected] Culture Media Mr Peter Traynor Oxoid Australia Pty Limited 20 Dalgleish Street, Thebarton SA 5031 Tel 1800 33 11 63 Email [email protected] Education Dr Chris Burke Degree Coordinator National Centre for Marine Conservation and Resource Sustainability University of Tasmania, Locked Bag 1370 Launceston TAS 7250 Tel (03) 6324 3806 Fax (03) 6324 3804 Email [email protected] Food Microbiology Sofroni Eglezos Technical Manager EML Consulting Services Qld Pty Ltd 1/148 Tennyson Memorial Avenue Tennyson QLD 4105 Tel (07) 3848 3622 Fax (07) 3392 8495 Mobile 0410 664 530 Email [email protected] www.eml.com.au Laboratory Management Captain Dennis Mok, MASM 2nd Division, Randwick Barracks Randwick NSW 2031 Email [email protected] Microbial Ecology Dr John Bowman University of Tasmania Antarctica CRC GPO Box 252-80, Hobart TAS 7001 Tel (03) 6226 2776 Email [email protected] Microbial Informatics AProf Michael Wise University of Western Australia Biochemistry M310 35 Striling Highway, Crawley WA 6009 Tel 08 6488 4410 Fax 08 6488 1148 Email [email protected] Probiotic & Enteric Microbial Diversity SIG Dr James Chin, NSW Agriculture PO Box 128, Glenfield NSW 2167 Tel (02) 4640 6359 Email [email protected] Rapid Methods Vacant Students Convenor Si Ming Man PhD Candidate, School of Biotechnology & Biomolecular Sciences University of New South Wales Sydney, NSW 2052 Tel (02) 9385 3514 Fax (02) 9385 1483 Email [email protected] Division 4 Molecular Microbiology Dr Peter Lewis School of Environmental & Life Sciences University of Newcastle Callaghan NSW 2308 Tel (02) 4921 5701 Fax (02) 4921 6923 Email [email protected] MICROBIOLOG Y A U STRA LIA • N OV EM BER 2008
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