Tuberculosis

Tuberculosis

TB is a bacterial infection. Anyone can catch TB by breathing in the bacteria that cause it. Bacteria are present in tiny droplets coughed out by someone who has TB.

Some people become ill with TB. This is called 'active' TB. People can become ill within a few weeks, months or years of breathing in the bacteria. In most people, the body's immune system kills the bacteria and the person doesn't get ill.

In other people, the bacteria aren't killed but stay in the body at a low level, so the person doesn't get ill and isn't infectious. This is called 'latent' TB. If the bacteria start to multiply again months or years later the person could develop active TB. This sometimes happens, for example, if the person's immune system is weakened by another disease such as HIV or treatments such as drugs for cancer.

Active TB mainly affects the lungs, but it can affect other parts of the body, such as the lymph nodes (glands), brain or spinal cord. The most common symptoms of TB include a persistent cough, extreme tiredness, loss of appetite, weight loss, fever and night sweats.

TB is curable, but it is important that both active and latent TB are treated quickly. This is to avoid the bacteria spreading through the body and to other people.