Tuberculosis (TB) is an infectious disease that is caused by a bacterium called Mycobacterium tuberculosis. It primarily affects the lungs, but it can also affect organs in the central nervous system, lymphatic system and circulatory system among others. When a person becomes infected with TB, the bacteria in the lungs multiply causing pneumonia; the patient experiences chest pain and has a persistent cough which often brings up blood.

Types of TB are - 1. Latent TB - the bacteria are inactive but present in the body.
2. Active TB - the bacteria are active and make the patient ill.

BCG Vaccine usually protects children and infants from TB.

Symptoms : unexplained weight loss, fatigue, shortness of breath, fever, night sweats, chills, loss of appetite etc.