Tuberculosis (TB)

Tuberculosis (TB)

(Updated on 14 June 2024)

Tuberculosis (TB) is caused by Mycobacterium tuberculosis, these bacteria usually attack the lungs, but can also attack any part of the body such as the kidney, spine, and brain. Every year, 10 million people fall ill with tuberculosis (TB). Most of the people who fall ill with TB live in low- and middle-income countries, but TB is present all over the world. 

Despite being a preventable and curable disease, 1.5 million people die from TB each year – making it the world’s top infectious killer.  Not everyone infected with TB bacteria becomes sick. As a result, two TB-related conditions exist: latent TB infection (LTBI) and TB disease. About 5–10% of people infected with TB will eventually get symptoms and develop TB disease. Those who are infected but not (yet) ill with the disease cannot transmit it. TB disease is usually treated with antibiotics and can be fatal without treatment.

Tuberculosis spreads easily where people gather in crowds or where people live in crowded conditions.  Tuberculosis can spread when a person with the illness coughs, sneezes, or spit. This can put tiny droplets with the germs into the air. A person needs to inhale only a few germs to become infected.

Common symptoms of TB:

  • Fever
  • Night sweats
  • prolonged cough (sometimes with blood)
  • chest pain
  • weakness and fatigue
  • weight loss.

People infected with TB bacteria have a 5–10% lifetime risk of falling ill with TB. People with HIV/AIDS and other people with weakened immune systems have a higher risk of catching tuberculosis than people with typical immune systems.

Certain conditions can increase a person’s risk for tuberculosis disease:

  • diabetes
  • weakened immune system (for example, HIV or AIDS)
  • being malnourished
  • tobacco use.


  • Seek medical attention if you have symptoms like prolonged cough, fever and unexplained weight loss as early treatment for TB can help stop the spread of disease and improve your chances of recovery.
  • Get tested for TB infection if you are at increased risk, such as if you have HIV or are in contact with people who have TB in your household or your workplace.
  • If prescribed treatment to prevent TB, complete the full course.
  • If you have TB, practice good hygiene when coughing, including avoiding contact with other people and wearing a mask, covering your mouth and nose when coughing or sneezing, and disposing of sputum and used tissues properly.

In certain countries, the Bacille Calmette-Guérin (BCG) vaccine is given to babies or small children to prevent TB. The vaccine prevents TB outside of the lungs but not in the lungs.

United Nations personnel are exposed to the risk of contracting TB by virtue of their work in some of the countries where the disease is endemic. In order to reduce the risk of UN personnel and their dependents from contracting TB, please consult the DHMOSH Guidance for the Prevention and Management of Latent and Active Tuberculosis (English / French). These recommendations will be updated as new information and guidance become available.

To learn more about Tuberculosis and TB in your regions, please visit:  WHO Tuberculosis Fact sheet