Leishmaniasis

The leishmaniases are a group of diseases caused by protozoan parasites from more than 20 Leishmania species. These parasites are transmitted to humans by the bite of an infected female phlebotomine sandfly, a tiny – 2–3 mm long – insect vector.

There are three main forms of the disease: cutaneous leishmaniasis (CL), visceral leishmaniasis (VL), also known as kala-azar, and mucocutaneous leishmaniasis (MCL). CL is the most common form, VL is the most severe form and MCL is the most disabling form of the disease.

Most people who become infected with the parasite do not develop any symptoms during their lifetime. Therefore, the term leishmaniasis refers to the condition of becoming sick due to a Leishmania infection, not to being infected with the parasite.

In 2018, 92 and 83 countries or territories were considered endemic for, or had previously reported cases of, CL and VL, respectively.

Today, more than 1 billion people live in areas endemic for leishmaniasis and are at risk of infection. An estimated 30 000 new cases of VL and more than 1 million new cases of CL occur annually