ABSTRACT

From eld and laboratory observations, it is evident that there is a close evolutionary t between Leishmania species and their sand y vectors (Killick-Kendrick, 1985). This translates into an observed restricted vector competence in certain sand ies such as Phlebotomus papatasi. Despite its wide distribution and prevalence in foci with more than one Leishmania species, P. papatasi has only been found infected with Leishmania major strains. This natural speci city was further characterized by the loss of experimental infections of P. papatasi with all tested species of Leishmania apart from L. major (Killick-Kendrick et al., 1994; Pimenta et al., 1994). Phlebotomus sergenti, a natural vector of Leishmania tropica also shares this speci city (Killick-Kendrick et al., 1995; Kamhawi et al., 2000). In contrast, natural vectors of visceral leishmaniasis such as Lutzomyia longipalpis, Phlebotomus argentipes, and Phlebotomus halepensis exhibit the opposite phenotype supporting maturity experimental infections with various Leishmania species including L. major and L. tropica (Pimenta et al., 1994; Sadlova et al., 2003). Studies aimed at elucidating this observed vector-parasite speci city focused on Leishmania glycoconjugates and their interaction with the sand y midgut to which the parasite’s life cycle is restricted.