Leishmaniasis

Leishmaniasis is a parasitic infection spread by sandflies, which feed on humans and then inject parasites called mastigotes into the bloodstream or skin. These parasites then reproduce, causing the symptoms. Leishmaniasis occurs in three forms:

• Visceral: a chronic wasting illness also known as kala azar.

• Cutaneous: a skin disorder which results in ulceration.

• Mucocutaneous: lesions of the mucous membranes in the nose, mouth and throat.

The three forms are spread by separate types of sandflies.

All types occur in parts of India, China, Russia, Africa and South America, and also in Spain, Italy and southern France. Visceral leishmaniasis can be contracted in southern Europe, and can also be transmitted from one person to another. The countries most severely affected by visceral leishmaniasis are Brazil, Bangladesh, India, Nepal and Sudan, which account for 90% of reported cases each year.

Cutaneous leishmaniasis occurs most frequently in Brazil, Peru, Iran, Saudi Arabia, Afghanistan and Syria. Mucocutaneous leishmaniasis occurs most frequently in Bolivia, Brazil and Peru.

HIV and leishmaniasis co-infection has been reported most frequently in southern Europe and in Brazil, but the World Health Organization has suggested that if surveillance were better, it is likely that high levels of co-infection would also be detected in east Africa.

Leishmaniasis may be acquired during the first few decades of life and either be controlled but not cleared, or may lie dormant until HIV infection occurs. The suppression of the immune system can allow leishmaniasis to develop.