Diseases like tuberculosis and leprosy are classified as bacterial diseases. This classification is based on the fact that both diseases are caused by bacteria, which are single-celled microorganisms.
Tuberculosis is caused by a bacterium known as Mycobacterium tuberculosis. This bacterium primarily affects the lungs but can also infect other parts of the body such as the kidneys, spine, and brain.
Leprosy, also known as Hansen's Disease, is caused by a different bacterium named Mycobacterium leprae. This bacterium primarily affects the skin, nerves, and mucous membranes, leading to severe disfigurement if untreated.
Both of these diseases are considered infectious, meaning they can be spread from person to person, although leprosy is much less contagious than tuberculosis. The emphasis on bacterial origin classifies these conditions under bacterial diseases, distinguishing them from parasitic, fungal, and viral diseases, which are caused by parasites, fungi, and viruses respectively.