Photograph a Phlebotomus papatasi sand fly.

Phlebotomus papatasi sand fly.


Phlebotomus papatasi sand fly.

Credit: CDC

Leishmaniasis is a parasitic disease transmitted by the bites of infected sand flies. It is found in nearly 88 countries, from rain forests in Central and South America to deserts in the Middle East and west Asia. Some cases of the disease have also appeared in Mexico and Texas. The disease takes several different forms, including the most common cutaneous leishmaniasis, which causes skin lesions, and the more severe visceral leishmaniasis (also known as kala azar), which affects internal organs such as the spleen, liver, and bone marrow. 

Why Is the Study of Leishmaniasis a Priority for NIAID?

The World Health Organization estimates there are between 600,000 and 1 million new cases of cutaneous leishmaniasis and 50,000-70,000 new cases of visceral leishmaniasis in the world each year. Leishmaniasis not only affects people who live in countries where the disease is endemic but also poses a risk to people who travel in those areas. According to the World Health Organization (WHO), 90 percent of all cutaneous leishmaniasis cases occur in Afghanistan, Brazil, Iran, Peru, Saudi Arabia, and Syria.

How Is NIAID Addressing This Critical Topic?

NIAID conducts and supports leishmaniasis research to advance the understanding of all aspects of the disease, including the different species of disease-causing Leishmania parasites, the varieties and biology of sand flies that transmit the parasites to animals and humans, and how the host immune system responds to the infection.  NIAID also supports development of therapeutics for treatment.

To learn about risk factors for leishmaniasis and current prevention and treatment strategies visit the MedlinePlus leishmaniasis site.

Parasite & Vector

NIAID scientists are researching different species of disease-causing Leishmania parasites and the varieties and biology of sand flies that transmit the parasites to animals and humans.

Read more about leishmaniasis parasite and vector


NIAID has a research program focused on designing vaccines that confer long-term protection from diseases that require cell-mediated immunity in humans, such as tuberculosis and leishmaniasis.

Read more about leishmaniasis vaccines
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