What is tuberculosis?
Tuberculosis (TB) is a disease caused by a slow-growing bacteria called Mycobacterium tuberculosis. Active TB disease can occur weeks, months or years after you are infected by breathing in the TB bacteria form an infectious person.
In most people, despite inhaling the TB bacteria, the immune system controls the TB bacteria which remains in the body in a dormant state, is not contagious and never causes symptoms. This is called latent TB.
However in about five to ten out of every 100 people with latent TB, the bacteria can start to multiply again or reactivate and lead to symptoms of active TB. This is called active TB disease.
TB can affect any part of your body, not just the lungs. In the UK, just over half of people with active TB have TB in their lungs. TB can affect other parts of your body such as the lymph glands, bones, gut, kidney or brain.
What can increase the risk of TB?
You have a higher risk of developing active TB if:
- You come into contact of a case of infectious lung TB, especially if recent
- You have HIV
- You were born in a country of medium or high TB incidence or resided in one for over 3 months
- You have previously had TB
- You have chronic kidney disease
- You have type 2 diabetes
- You have an alcohol or drug addiction
- You are on medication that suppresses the immune system (such as anti-rheumatoid agents/ transplant rejection medication)
What are the symptoms of TB?
Symptoms of active TB include:
- A cough lasting more than 3 weeks
- Unexplained weight loss
- Night sweats
- Coughing up sputum or blood
How is TB treated?
Active TB disease is treated with a combination of antibiotics for 6 months.
Latent TB infection can be treated with a preventative course of antibiotics in those with a higher chance of progression to developing active TB disease.