Leprosy is an infectious disease that has been known since biblical times. It is characterized by disfiguring skin sores, nerve damage, and progressive debilitation.
Causes, incidence, and risk factors
Leprosy is caused by the organism Mycobacteriumleprae. It is not very contagious (difficult to transmit) and has a long incubation period (time before symptoms appear), 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 sores on the skin, but the lepromatous form is most severe, producing large, disfiguring lumps and bumps (
All forms of the disease eventually cause nerve damage in the arms and legs, which causes
Leprosy is common in many countries worldwide, and in temperate, tropical, and subtropical climates. Approximately 100 cases per year are diagnosed in the United States. 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, has led to global concern about this disease.
Review Date: 08/28/2009
Reviewed By: Linda Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine; Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School, Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.