Natural Trypanosoma cruzi Infection in Triatomines (Hemiptera: Reduviidae: Triatominae) in an Ecotourism Area of the Atlantic Forest in São Paulo State.

Background: Triatomines (Hemiptera: Reduviidae: Triatominae), which are the vectors of Chagas disease in Brazil, are associated with forested areas. This study analyzed triatomines and their natural infection by Trypanosoma cruzi in an Atlantic Forest remnant in the state of São Paulo, Brazil. Materials and Methods: Thirty-five triatomines were captured and identified as Triatoma tibiamaculata and Panstrongylus megistus. The study included direct trypanosome research and isolation in Balb/c mice. Results: Fifteen isolates were obtained from seven triatomines representing both species. Protein sequences from the V7-V8 SSUrDNA region were obtained from the isolates and positive triatomines and were analyzed using maximum parsimony and Bayesian methods for phylogenetic positioning. All sequences obtained were identified as T. cruzi; the isolates were classified as TcII, whereas a direct sample was typed as TcIV. Conclusion: The results demonstrated the occurrence of active transmission cycles and the risk of vector transmission to the population in these regions.