Tuberculosis (TB) is a disease caused by bacteria that are spread through the air from person to person. If not treated properly, TB disease can be fatal. People infected with TB bacteria who are not sick may still need treatment to prevent TB disease from developing in the future.
The TB bacteria are put into the air when a person with TB disease coughs, sneezes, speaks, or sings. People nearby may breathe in these bacteria and become infected. There are two types of TB conditions: latent TB infection and TB disease.
TB bacteria most commonly grow in the lungs, and can cause symptoms such as:
A bad cough that lasts 3 weeks or longer
Pain in the chest
Coughing up blood or sputum (mucus from deep inside the lungs)