Leishmaniasis is a parasitic disease endemic in 88 countries and affecting over 12 million people. It principally affects poor, remote communities where there is limited access to healthcare and affordable drugs. Leishmaniasis often occurs as an epidemic, especially when previously unexposed populations are forced by war and famine to move into endemic areas. The parasite is transmitted to humans by biting sand flies.
In the most severe form of the disease, the visceral leishmaniasis also called kala azar, the parasite attacks the visceral organs such as the liver and spleen. It also attacks the immune system and, without treatment, kala azar is fatal in almost 100% of cases. Over 90 percent of visceral leishmaniasis cases occur in five countries: Bangladesh, Brazil, India, Nepal and Sudan.
Diagnostic tests for leishmaniasis are invasive and potentially dangerous, and require lab facilities and specialists not readily available in resource-poor settings. With proper treatment, approximately 92 percent of people infected can be cured. But many of the available drugs have drawbacks, including the length of treatment (30 days), toxicity and cost. Drug resistance is also a problem, especially in India where as many as 65% of patients are infected with resistant Leishmania.