Mycobacterial disease refers to infections caused by bacteria from the genus Mycobacterium. The most well-known type is tuberculosis (TB), which primarily affects the lungs but can also impact other parts of the body. These bacteria are slow-growing and can remain dormant in the body for long periods, making diagnosis and treatment challenging. Another significant mycobacterial disease is leprosy, caused by Mycobacterium leprae. This disease affects the skin, nerves, and mucous membranes, leading to disfigurement and disability if left untreated. Both diseases are typically spread through respiratory droplets or prolonged contact with an infected person, highlighting the importance of public health measures in prevention.