TB is caused by the bacterium Mycobacterium tuberculosis. TB usually affects the lungs, known as pulmonary TB, but may affect almost any other part of the body, known as extra-pulmonary TB.

WHAT ARE THE SYMPTOMS OF TB?

The most common symptom of Tb is a persistent, productive cough usually for more than 2 weeks. Other constitutional symptoms include persistent fever, unexplained weight loss, night sweats, anorexia (loss of appetite) and fatigue.

Other respiratory symptoms may include shortness of breath, chest and back pain and haemoptysis.
Symptoms of extrapulmonary TB are related to specific extrapulmonary sites such as lymph nodes, pleura, larynx, meninges, genito-urinary, intestinal tract, bone, spinal cord and skin.

HOW IS TB SPREAD?

TB is spread through aerosolized droplets after infected people cough, sneeze or even speak. People nearby, if exposed long enough, may breathe in bacteria in the droplets and become infected.

When a person breathes in TB bacteria, the bacteria settle in the lungs. If that person's immune system is compromised, or becomes compromised, the bacteria begin to multiply. From the lungs, they can move through the blood to other parts of the body, such as the kidney, spine and brain. TB in these other parts of the body is usually not infectious.