Tuberculosis is a global health problem, infecting one third of the world's population and causing millions of deaths annually. It is the 6th highest cause of disease in Pakistan, where the incidence of active TB cases is over 80 per 100,000 people each year. TB is caused by the bacterium Mycobacterium tuberculosis, which is transmitted through the air when people with active TB cough or sneeze. It most often affects the lungs but can damage other organs. While the immune system usually keeps the infection under control, active disease can develop if the bacteria overpowers immunity.