Molecular characterization of Trypanosoma cruzi samples derived from Triatoma vitticeps and Panstrongylus geniculatus of the Atlantic rainforest, southeast Brazil

Abstract

Background: In rural areas of Espírito Santo state, southeast Brazil, triatomine species attracted by light frequently invade residences. The aim of this study was to investigate the Trypanosoma cruzi discrete typing units (DTUs) harbored by these triatomines. Methods: Triatomine’s intestinal contents were examined, inoculated in mice, and the positive samples were cultivated. Flagellates obtained from infected mice hemoculture were submitted to DNA extraction using a salting-out method and to TcSC5D gene amplification. The amplified samples were sequenced, and polymorphism was analyzed for DTU identification. Results: Three hundred and ninety-four triatomines were identified: Triatoma vitticeps (90.03%), Panstrongylus geniculatus (8.89%), Panstrongylus megistus (0.54%), Panstrongylus diasi (0.27%), and Triatoma tibiamaculata (0.27%). Among the specimens, 251/394 (67.65%) presented flagellated forms similar to T. cruzi. After triatomine intestinal content inoculation into mice, 134 mice presented T. cruzi-like trypomastigotes from Tr. vitticeps and P. geniculatus and 89 samples were positive in hemoculture. Sixty-two samples were analyzed for the TcSC5D gene and TcI, TcII, TcIII, and TcIV DTUs were identified. Conclusions: We observed T. cruzi DTU diversity in Tr. vitticeps and P. geniculatus, which showed the predominance of TcII and occurrence of TcI, TcIII and TcIV. Triatomines presented high T. cruzi infection rates. Since little is known regarding the possible mammalian hosts that maintain the T. cruzi cycle, further studies are necessary to obtain a better understanding of the parasite transmission cycle in this region.

Wild Mammal Translocations: A Public Health Concern

“…In addition, it was capable to maintain long term infection by the same lineage of the parasite, and have been frequently described in natural infection, with corroborates with the possibility of vector dispersion [42].…”

Systematic review on the biology, ecology, genetic diversity and parasite transmission potential of Panstrongylus geniculatus (Latreille 1811) in Latin America

“…Brazilian rates are 16.5%, (154) 50%, (155) 4.7% (156) and 27.3%. (157) The Trinidadian rate is 42.5%, (80) the Colombian rates are 50%, (40) 70.6% (93) and 58.3%, (118) the Venezuelan rates are 20% (138) and 76.1%, (128) the Peruvian rate is 50%, (120) and the Bolivian rate is 62.5%. (51) Currently, seven DTUs, TcI to TcVI and T.c.bat, are known to circulate in the vectors in different proportions.…”

“…(51) In Brazil, insects infected with TcII and TcIII have been identified. (157) In Colombia, the transmission dynamics of the primary and secondary vectors in six departments (Antioquia, Cesar, Guajira, Huila, Meta, and Norte de Santander) were studied and, with six circulating DTUs (TcI, TcII, TcIII, TcIV, TcV and TcVI). P. geniculatus was observed to be the species with the highest number of DTUs.…”

“…Brazilian rates are 16.5%, 154 50%, 155 4.7% 156 and 27.3%. 157 The Trinidadian rate is 42.5%, 80 the Colombian rates are 50%, 40 70.6% 93 and 58.3%, 118 the Venezuelan rates are 20% 138 and 76.1%, 128 the Peruvian rate is 50%, 120 and the Bolivian rate is 62.5%. 51…”

First genotyping of Trypanosoma cruzi from naturally infected Triatoma juazeirensis, Triatoma melanica and Triatoma sherlocki from Bahia State, Brazil

“…In the present paper we could demonstrate other Triatoma taxa harbouring both TcI and TcII, emphasizing a possibly important role of these triatomine species in the T. cruzi transmission cycles. Natural and experimental infections of other triatomine species like Triatoma vitticeps or Triatoma infestans have also been documented (Padilla et al ., 2017; Dario et al ., 2018). In contrast, certain TcII genotypes are not able to establish, show a weaker population growth dynamic or produce metacyclic trypomastigote forms under specific conditions in R. prolixus (Perlowagora‐Szumlewicz & Moreira, 1994; Mello et al ., 1996; Araújo et al ., 2007, 2014).…”