Leprosy

Overview, Causes, & Risk Factors

Leprosy is caused by the organism Mycobacteriumleprae. It is a difficult disease to transmit and has a long incubation period, which makes it difficult to determine where or when the disease was contracted. Children are more susceptible than adults to contracting the disease.

Leprosy has two common forms, tuberculoid and lepromatous, and these have been further subdivided. Both forms produce lesions on the skin, but the lepromatous form is most severe, producing large disfiguring nodules.

All forms of the disease eventually cause peripheral neurological damage (nerve damage in the extremities) manifested by sensory loss in the skin and muscle weakness. People with long-term leprosy may lose the use of their hands or feet due to repeated injury resulting from lack of sensation.

Leprosy is common in many countries in the world, and in temperate, tropical, and subtropical climates. Approximately 100 cases per year are diagnosed in the U.S. Most cases are limited to the South, California, Hawaii, and U.S. island possessions.

Effective medications exist, and isolation of victims in "leper colonies" is unnecessary. The emergence of drug-resistant Mycobacterium leprae, as well as increased numbers of cases worldwide, have led to global concern about this disease.