- an infectious bacterial disease characterized by the growth of nodules (tubercles) in the tissues, especially the lungs.
- The disease is caused by the bacterium Mycobacterium tuberculosis or (especially in animals) a related species; Gram-positive acid-fast rods
The most common form, pulmonary tuberculosis (formerly known as ‘consumption’), is caused by inhalation of the bacteria. It was widespread in 19th-century Europe, and still causes 3 million deaths each year in developing countries. The disease can affect other parts of the body, notably the bones and joints and the central nervous system. Its spread was largely countered by vaccination and by the pasteurization of milk to prevent transmission from cattle. Today, the rise in HIV has helped cause a resurgence of tuberculosis, especially of drug-resistant strains