Leishmania in phlebotomid sandflies. VII. On the taxonomic status of Leishmania peruviana , causative agent of Peruvian ‘uta’, as indicated by its development in the sandfly, Lutzomyia longipalpis

Abstract

The name L. peruviana was given by Velez (1913) to the parasite responsible for a form of [human] cutaneous leishmaniasis known as uta; this disease occurs in the Peruvian Andes. Clinical similarities between uta and oriental sore, which is caused by L. tropica of the eastern hemisphere, have led to the suggestion that uta is due to L. tropica, which was introduced into Latin America. Leishmania spp. are divisible into 3 distinct sections, according to their pattern of development in their natural (phlebotomine) vectors. One of these sections, the Peripylaria, contains the subspecies of L. braziliensis, and is characterized by parasites that undergo a phase of development attached to the wall of the hindgut (pylorus and ileum), in addition to multiplication in the midgut and subsequent invasion of the foregut. Such development is unknown in any other group of Leishmaniae, including those groups of the section Suprapylaria, which includes parasites of the L. tropica complex. Three isolates of L. peruviana were studied in laboratory-bred sandflies, Lutzomyia longipalpis (Lutz et Neiva), and all showed consistent and prolific development of rounded or stumpy flagellates. Development of both L. tropica and L. major, in the same insect, was restricted to development of free flagellates in the midgut. From the behavior of L. peruviana in the sandfly, its slow growth in hamster skin and the small size of its amastigotes, this parasite is distinctly different from both L. tropica and L. major, and closely related to subspecies of L. braziliensis within the section Peripylaria. L. peruviana is indigenous to the American continent. The specific name is retained for the time being (rather than L. braziliensis peruviana).