Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis and, less commonly, by other organisms of the "tuberculosis complex". Globally, it is estimated that 18 lac people die from TB each year--majority of them in developing countries. TB remains a major public health problem in India. Every year approximately 18 lac people develop TB and about 4 lac die from it. India accounts for one-fifth of global incidence of TB and tops the list of 22 high TB burden countries. TB kills more adults in India than any other infectious disease. In India, more than 40% of population is infected with TB bacilli.

TB affects the lungs in more than 85% of cases. This form of the disease is called pulmonary tuberculosis. TB of any organ other than the lungs, such as the pleura, lymph nodes, intestines, genitourinary tract, skin, joints and bones, meninges of the brain etc. is classified as extra-pulmonary tuberculosis. Globally, the HIV epidemic is worsening the situation, increasing the number of tuberculosis cases and accelerating the spread of the disease.