- A genus of protozoa comprising parasites of worldwide distribution, several species of which are pathogenic for humans. All species are morphologically indistinguishable, and therefore the organisms have usually been assigned to species and subspecies according to their geographic origin, the clinical syndrome they produce, and their ecologic characteristics. They have also been separated based on their tendency to cause visceral, cutaneous, or mucocutaneous leishmaniasis. In some classifications, Leishmania is grouped in four complexes comprising species and subspecies: L. donovani, L. tropica, L. mexicana, and L. viannia.
- Leishmania is a genus of trypanosomes that are responsible for the disease leishmaniasis. They are spread by sandflies of the genus Phlebotomus in the Old World, and of the genus Lutzomyia in the New World. At least 93 sandfly species are proven or probable vectors worldwide. Their primary hosts are vertebrates; Leishmania commonly infects hyraxes, canids, rodents, and humans.