CONICET | Buscador de Institutos y Recursos Humanos

Laboratory of Eco-Epidemiology, Department of Ecology, Genetics and Evolution, Universidad de Buenos Aires, Buenos Aires, Argentina. 2 Department of Environmental Studies, Emory University, Atlanta, GA, USA. 3 Fogarty International Center, National Institutes of Health, Bethesda, MD, USA. Reservoirs of Trypanosoma cruzi include a wide variety of wild mammals such as marsupials, edentate and rodents. In this study we estimated the prevalence of T. cruzi in wild mammals in a rural area of Pampa del Indio (Chaco, Argentina). Four wild mammal surveys were conducted between August 2008 and March 2011. A total of 195 sylvatic mammals were captured and examined for infection. Twenty-seven (14,5%) animals were xenodiagnosis-positive, including 12 (29,3%) Didelphis albiventris opossums, 12 (46,1%) Dasypus novemcinctus, 2 (12,5%) Tolypeutes matacus armadillos, and one (6,3%) Chaetophractus vellerosus armadillo. All opossums were infected with the UDT TcI and all armadillos were infected with TcIII. Blood samples were also tested by kDNA-PCR and SAT-DNA-PCR. A total of 38 (20,3%) animals were found kDNA-PCR-positive: the xenodiagnosis-positive animals (except 1 Dasypus novemcinctus, 1 Didelphis albiventris and 2 Tolypeutes matacus); and 15 xenodiagnosis-negative animals (4 Didelphis albiventris opossum, 1 Euphractus sexcinctus armadillo, 5 Thylamys pusilla, 3 Dasypus novemcinctus and 2 small rodents). Through SAT-DNA-PCR we confirmed infection with T. cruzi in three animals positives only by kDNA-PCR: one Dasypus novemcinctus and two Thylamys pusilla. These are the first findings in Argentina of T. cruzi in Thylamys pusilla confirmed by kDNA-PCR and PCR-DNA-SAT; and TcIII in C. vellerosus and T. matacus. The study and monitoring of wild transmission cycles of T. cruzi will be great importance in areas under surveillance of Chagas disease such as Pampa del Indio in the Humid Chaco.