Vector Competence of Lutzomyia cruzi Naturally Demonstrated for Leishmania infantum and Suspected for Leishmania amazonensis

Corumba city is one of the oldest visceral leishmaniasis endemic foci in the state of Mato Grosso do Sul, Brazil, where the transmission of Leishmania infantum has been attributed to Lutzomyia cruzi. Aiming at investigating the parameters of the vectorial capacity of Lu. cruzi for L. infantum, a project was undertaken in this city. Among these parameters, vector competence was investigated and the results obtained are reported herein. Of the 12 hamsters exposed to feed wild-caught female sandflies, two developed infection with L. infantum and surprisingly, one with Leishmania amazonensis. In addition, hamsters with L. infantum infection were bitten only by females of Lu. cruzi, whereas the hamster infected with L. amazonensis was bitten by 124 Lu. cruzi females and one of Evandromyia corumbaensis. Although there is a strong suspicion regarding the competence of Lu. cruzi in transmitting L. amazonensis naturally, it was not demonstrated.