"Leishmania" is a descriptor in the National Library of
Medicine's controlled vocabulary thesaurus, MeSH (Medical
Subject Headings). Descriptors are arranged in a hierarchical
structure, which enables searching at various levels of
specificity. A genus of flagellate protozoa comprising several
species that are pathogenic for humans. Organisms of this genus
have an amastigote and a promastigote stage in their life
cycles. As a result of enzymatic studies this single genus has
been divided into two subgenera: Leishmania leishmania and
Leishmania viannia. Species within the Leishmania leishmania
subgenus include: L. aethiopica, L. arabica, L. donovani, L.
enrietti, L. gerbilli, L. hertigi, L. infantum, L. major, L.
mexicana, and L. tropica. The following species are those that
compose the Leishmania viannia subgenus: L. braziliensis, L.
guyanensis, L. lainsoni, L. naiffi, and L. shawi. - Leishmania
viannia - Leishmania viannias - viannia, Leishmania - viannias,
Leishmania - Leishmania (Viannia) - Leishmanias (Vi