What Is Leprosy (Hansen’s Disease): Cause, Facts, Epidemiology

What Is Leprosy?

Leprosy is a chronic infection caused by bacterium Mycobacterium leprae that usually affects skin, peripheral nerves (usually in the limbs and face), upper airways and eyes. Another name for leprosy is Hansen’s disease (after Dr. G.A. Hansen who discovered it in 1873) (1).

The first sign of a disease is usually one or more discolored patches of the skin with reduced sensibility. Later, disfiguring plaques and nodules may appear. Because of damaged nerves in the limbs, affected person may lose a sense of touch and pain and may not be aware of injuries what may in long term lead to permanent damage of limbs.

Epidemiology and World Distribution

Leprosy remains a public health problem in India, Nepal, Myanmar, Madagascar, Brazil, Angola, Central African Republic, Democratic Republic of Congo, Madagascar, Mozambique and the United Republic of Tanzania (3).

No cases of leprosy was reported from Europe, North America, central and north Asia and Australia on the beginning of y. 2007 (4).

Leprosy is supposedly (not certainly) transmitted through nasal or mouth droplets or skin to skin contact. Many infected patients are not contagious at all. Most of healthy persons have natural immunity against leprosy and will never develop a disease (2). Both children and adults may be affected. Leprosy is not a genetic disease. Isolation of patients with leprosy is not necessary. Travelers are at no realistic risk to contract leprosy during visiting affected countries.

Leprosy can be successfully treated with antibiotics. Leprosy is rarely deadly even if untreated.

Related Articles:


  1. Leprosy – the cause and forms (niaid.nih.gov)
  2. Leprosy transmission (doh.gov.ph)
  3. Countries affected by leprosy (who.int)
  4. Leprosy on the World map in 2007 (who.int)
About Jan Modric (249 Articles)
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  • Jan Modric

    To shellia gay.

    For more info you can check reference links on the bottom of the article.