Tuberculosis
Tuberculosis (TB) is rare in the UK and most people don’t need to worry about it, particularly if their health is generally good. It most often affects the lungs and is caused by a type of airborne bacteria (Mycobacterium tuberculosis). It spreads through the air when infectious people cough or sneeze.
TB is fully treatable and curable with a course of antibiotics and people are no longer infectious after 2 weeks of treatment. Testing and treatment are free and confidential in the UK.
It can be latent or active. Someone with latent TB doesn’t have symptoms and can’t pass the disease on but may go on to develop active TB at some point.
Someone with active TB does have symptoms and can pass the disease to other people.
However, a lot of time in close contact with an infected individual is needed for it to be passed on.
The greatest risk of catching TB is through spending a lot of time with people who have TB bacteria in their lungs or throat in the period before diagnosis, and before 2 weeks of treatment have been completed.
Therefore, the people at greatest risk of catching TB are those that live with the infected person.
In workplaces or schools, people do spend periods of time together so there is some potential risk of transmission, however, this level of contact has a much lower risk compared to contact in the home setting.
The risk of developing TB after contact with a case is very low and it is unusual for those in contact with TB to develop active (infectious) TB themselves. 1 in 10 people in contact with TB acquire latent TB - this is not infectious, is not a public health risk and has no symptoms. Latent TB can be treated, even though it is not infectious, to prevent active TB developing later in life.
Symptoms
Early diagnosis and treatment mean that an individual recovers sooner and reduces the risk of any long-term damage to their body. The risk of transmission also reduces.
The symptoms of TB can appear slowly, and an individual may not have all of them.
Anyone who suspects they may have active TB should speak to their GP.
The symptoms are:
- a cough that lasts more than 3 weeks - you may cough up mucus (phlegm) or mucus with blood in it
- feeling tired or exhausted
- a high temperature or night sweats
- loss of appetite
- weight loss
- feeling generally unwell
Testing or screening for TB
Screening for TB involves a simple health questionnaire and a blood test to see if a person has been exposed to TB. Because TB is a slow growing disease, the tests need to be done at the appropriate time, usually about 6 to 8 weeks after a person has come into regular and lengthy contact with an infected individual.
The Interferon gamma release assay (IGRA) is a blood test for TB (to see whether a person has been exposed to the tuberculosis bacteria).
In the event of someone presenting with symptoms of TB, further tests will be arranged which would most likely include a chest x-ray and samples of phlegm.
Treatment of Active TB
A course of antibiotics will usually need to be taken for 6 months. Once treated, the chance of any reinfection is extremely low.
Further information
Last updated 26 April 2024