Tuberculosis (TB) factsheet What is TB? Tuberculosis, or TB, is a disease caused by a germ (called the tubercle bacterium or Mycobacterium tuberculosis). TB usually affects the lungs, but can affect other parts of the body. Only some people infected with the TB germ go on to develop TB disease. TB is curable with a full course of treatment. How do you catch it? The TB germ is usually spread in the air. It is caught from another person who has TB of the lungs. The germ gets into the air when that person coughs or sneezes. But only some people with TB in the lungs are infectious to other people. Such cases are called ‘sputum smear positive’ (or “open” TB). Even then, you need close and prolonged contact with them to be at risk of being infected. Sputum smear positive cases stop being infectious after a couple of weeks of treatment. Can anyone get it? Anyone can get TB but it is difficult to catch. You are most at risk if someone living in the same house as you catches the disease, or a close friend has the disease. What are the symptoms? TB disease develops slowly in the body, and it usually takes several months for symptoms to appear. Any of the following symptoms may suggest TB disease:     Fever and night sweats Persistent cough lasting more than four weeks Losing weight without dieting Blood in the sputum (phlegm or spit) How is TB treated? TB can be cured by taking a course of antibiotics for around six months. What should I do if I think I might have TB? Visit your family doctor or call NHS Direct (0845 46 47) for advice. What is the difference between being infected with the TB germ and having TB disease? The majority of exposed people will kill off the inhaled TB germs. Sometimes, not all of the germs are destroyed and the person can become infected. But in most of these infected people, the body is able to contain the infection and stop the germs from growing. The germs become inactive, but they remain alive in the body and can become active later. Most people who have been infected with the TB germ will never develop TB disease. In these people, the TB bacteria remain inactive for a lifetime without causing disease. But in other people the bacteria may become active and cause TB disease. People infected by the TB germ without TB disease:      Have no symptoms Don’t feel sick Cannot spread TB to others Usually have a positive skin test reaction Can develop TB disease later in life What is done after exposure to someone with tuberculosis? When someone is diagnosed with TB a team of specialist health professionals will make an assessment of the infection risk to others and their close contacts will be investigated to identify others who may have been infected. If you are identified as a contact at risk from TB then you will be routinely invited for screening. Tests used for screening include an ‘interferon gamma release assay’ (IGRA) blood test (see below), Mantoux skin test or Chest Xray. People who have evidence of TB infection found from the blood test, skin test or chest X-ray, or those who are unwell, will be referred to a specialist doctor for further assessment and possible treatment course of anti-TB medication. Can TB be prevented? Yes it can. Most important is early detection, especially of infectious cases, and complete treatment of those cases to prevent spread. In some high-risk groups, BCG vaccination can offer some protection against TB but overall, BCG vaccination plays a limited role in TB control. Why was the BCG school immunisation programme discontinued? In the early 1950’s, there were over 50,000 cases of TB per year in the UK. The disease occurred across all sectors of society, but most cases occurred in younger adults, possibly related to more crowded working environments at that time which resulted in more people being exposed to the TB bacteria. BCG vaccine was introduced in the UK in 1953 and was offered to all children aged 12 or 13 years to provide protection before leaving school. The number of cases has fallen to less than 9,000 cases per year and TB now predominantly affects high risk communities, mainly because of their connections to higher-prevalence areas of the world. In other communities, factors such as homelessness and alcohol misuse are important risk factors. BCG vaccination is most effective at preventing severe disease in infants and young children. It is less effective in preventing respiratory disease, which is the more common form in adults. TB is difficult to catch and the main role of BCG is to protect those at high risk of exposure to TB. The lower the risks of TB infection, as occurs among the general population who do not belong to a high risk group, the lower the benefits of BCG. What is the interferon gamma release assay test (IGRA)? This is a blood test that can be used to help in the diagnosis of TB. It may be used in the diagnosis of TB infection or TB disease. The IGRA test is thought to be a more accurate test than the Mantoux skin test and will help determine whether you have been infected with TB, and therefore may need treatment. The test involves taking a single specimen of blood. Results will be available after 1-2 weeks. A positive result means that infection with TB is likely. A negative result means that infection with TB is unlikely. There are no significant risks associated with the test, apart from the minor discomfort of a blood test.