Leprosy may be defined as a chronic microbial ailment, caused by infectious bacteria namely, Mycobacterium lepromatosis and Mycobacterium leprae. Leprosy is an affliction of peripheral nerves and mucosal membrane of the upper respiratory tract.

The disease is named after physicist Gerhard Hansen. It is a communicable disease and is believed to be transmitted by respiratory droplets. However, it is not transmitted during sexual intercourse and is not highly infectious. It may affect people of any race, gender or age group, but it seldom affects infants. The incubation period of leprosy is usually few weeks, but there has been an evidence of the affliction lasting up to 30 years.

Leprosy leads to skin lesions and skin damage, which are the primary signs of the affliction. Leprosy may be broadly classified as Paucibacillary and multibacillary leprosy. The sub-categorization of leprosy is as under:

  • Tuberculoid leprosy is a kind of paucibacillary leprosy, characterized by one or more hypo pigmented skin macules, and anesthetic patches where skin sensation is lost due to damage of the peripheral nerves.
  • Borderline leprosy, a form of multibacillary leprory, is the most common of these afflictions and is of intermediate severity. The lesions and patches are similar to those seen in tuberculoid leprosy, but are irregular and greater in number.
  • Lepromatous leprosy is a type of multibacillary leprosy, characterized by secondary skin lesions, plaques, thickened dermis (skin), and nodules. This form of the ailment affects the nasal mucosa, leading to nasal congestion and nose bleeding (epistaxis). However, detectable nerve damage is usually delayed.
Alternative Names: Hansen's disease