Molecular characterization of Trypanosoma cruzi and Leishmania spp. coinfection in mammals of Venezuelan coendemic areas.

BACKGROUND & OBJECTIVES Trypanosoma cruzi and Leishmania spp. are protozoans that cause American trypanosomiasis and leishmaniasis, respectively. In endemic foci where both diseases coincide, coinfection can occur. The objective of this work was the characterization of the parasites involved in coinfection in several endemic areas of Venezuela. METHODS Molecular characterization was done in 30 samples of several species of mammals (Didelphis marsupialis, Equus mulus, Rattus rattus, Canis familiaris, Felis catus, and Sciurus granatensis) from the states of Anzoategui, Cojedes and Capital District diagnosed with T. cruzi and Leishmania spp. coinfections. For the typing of T. cruzi DTUs, the markers of miniexon, 24Sa rDNA, 18Sa rDNA, and hsp60-PCR-RFLP (EcoRV) were used. Infection by Leishmania spp. was characterized by miniexon multiplex PCR for complexes of Leishmania and ITS1-PCR-RFLP (HaeIII, HhaI, and RsaI) for the identification of the species. RESULTS The T. cruzi TcI was present in 100% of the coinfected mammals, which included 76.7% of triple infection by T. cruzi TcI-complex-L. (L) mexicana-L. infantum/chagasi, 13.3% of double infection by T. cruzi TcI-L. mexicana and 10% of double infection by T. cruzi Tcl-L. infantum/chagasi. INTERPRETATION & CONCLUSION These results suggest that the double or triple infection is a phenomenon existing in almost all the coendemics areas and mammals studied, which might influence the mechanisms of adaptation and pathogenicity of these parasites.