Leishmaniasis is primarily a skin disease produced by a number of different species of protozoa (genus Leishmania). The disease occurs in three basic clinical forms, each of which has several variants caused by different species, subspecies, or strains of the pathogen. The intermediate host is the sandfly.

Distribution and Incidence

Cutaneous leishmaniasis (often called “oriental sore”) is found in Armenia, Azerbaijan, Turkmenistan, Uzbekistan (republics of the former Soviet Union), Afghanistan, India, Iran, much of the Middle East and North Africa, the Sahara, the savanna states from Sudan to Senegal, and in Kenya and Ethiopia. In the New World, species of Leishmania cause various clinical forms of the disease in Central America, the Amazon Basin, the Guyanas, and the Andes, especially Venezuela and Peru. In eastern South America a form of the disease mainly afflicting children extends from Argentina to Venezuela and north through Central America to Mexico.

Mucocutaneous leishmaniasis is restricted to the New World and occurs in Brazil, eastern Peru, Paraguay, Ecuador, Colombia, and Venezuela.

Visceral leishmaniasis is found in India, Burma, Bangladesh, China, Thailand, Somalia, Chad, Kenya, Gabon, Sudan, and Niger. A variant occurring primarily among children is spread over southern Europe, North Africa, and the Middle East as well as Romania and the southern part of the former Soviet Union.

As a result of high levels of disease in rodent and dog populations, leishmaniasis is so common in endemic areas that it leaves its mark on every inhabitant. Recent estimates indicate that some 12 million individuals have one form or another of this infection.