Characteristics of triatomine infestation and natural Trypanosoma cruzi infection in the state of Rio grande do norte, Brazil

Abstract

Introduction: Natural and artificial ecotope infestation by the kissing bug triatomines and their colonization and infection by Trypanosoma cruzi, the Chagas disease agent, were evaluated in nine municipalities of the State of Rio Grande do Norte, Brazil. Methods: Following identification, triatomine intestinal contents were analyzed by direct microscopic examination, xenoculture, and polymerase chain reaction (PCR) for parasite detection. Trypanosoma cruzi isolates were genotyped using three different markers. Results: Of 842 triatomines captured, 65% were Triatoma brasiliensis, 17.8% Triatoma pseudomaculata, 12.5% Panstrongylus lutzi, and 4.7% Rhodnius nasutus. Triatoma brasiliensis and P. lutzi adults were found in the intradomicile. T. brasiliensis, T. pseudomaculata, and R. nasutus nymphs and adults were found in the peridomicile and wild environment. Intradomiciliary and peridomiciliary infestation indexes were 5.6% and 33.7%, respectively. In the peridomicile, chicken coops were the most infested ecotope. The T. cruzi triatomine infection rate was 30.2%, of which PCR detected 29%. P. lutzi (78.1%), T. brasiliensis (24.5%), and T. pseudomaculata (22.7%) were the most infected species. TcII and III genotypes were detected in T. brasiliensis and TcIII in P. lutzi. Conclusions: T. brasiliensis was found in all environments and most ecotopes with high T. cruzi infection rates. High infection rates were also detected in T. pseudomaculata and P. lutzi, suggesting their role in the interchange between the wild and peridomestic transmission cycles. The combination of PCR, microscopic examination, and xenoculture contributed to improving T. cruzi infection evaluation in triatomine bugs. The TcII and TcIII genotypes were predominant in the study area.