ABSTRACT
The present study aimed to identify the triatomine species and evaluate Trypanosoma cruzi infection in insects captured in endemic areas of Pará State, Brazil. Triatomines were captured in nine rural communities in the municipality of São Domingos do Capim in August, September and December 2014 using active searches and Malaise and Noireau traps. Additionally, from 2014 to 2018, residents and community health agents submitted captured triatomines to the study team. The analysis of T. cruzi infection in the insects was performed by direct parasitological examination and nested-PCR. A total of 225 triatomines were captured and identified: Rhodnius robustus (n = 111), Rhodnius pictipes (n = 54), Panstrongylus geniculatus (n = 44), Eratyrus mucronatus (n = 11), Panstrongylus lignarius (n = 4), and Panstrongylus rufotuberculatus (n = 1). Direct parasitological examination was performed in 27 living triatomines R. robustus (n = 14), P. geniculatus (n = 7) and R. pictipes (n = 6) and metacyclic trypomastigote forms similar to those of T. cruzi were observed in 66.6% (18/27) samples. Of 174 samples analysed by nested-PCR, 81.6% were positive for T. cruzi DNA: R. robustus (84.7%; 72/85), R. pictipes (84.1%; 37/44), P. geniculatus (69.4%; 25/36), P. lignarius (100%; 4/4), E. mucronatus (75%; 3/4) and P. rufotuberculatus (100%; 1/1). R. robustus, R. pictipes and P. geniculatus were the main vectors of T. cruzi in the studied areas; however, the detection of infections in P. lignarius, E. mucronatus and P. rufotuberculatus indicated that these species can also act as potential vectors of T. cruzi in the study areas.
Subject(s)
Chagas Disease , Rhodnius , Triatominae , Trypanosoma cruzi , Animals , Brazil/epidemiology , Chagas Disease/epidemiology , Chagas Disease/veterinary , Insect VectorsABSTRACT
Trypanosoma cruzi is the etiologic agent of American trypanosomiasis and can infect humans and different species of domestic and wild animals. The marsupials are important wild reservoirs of T. cruzi, aiding in the maintenance of this agent in sylvatic and peri-domestic environments. The objective of this study was to report the parasitological and clinicopathological findings of a natural infection by T. cruzi in one specimen of Philander opossum that originated from the Brazilian Amazon. The animal was captured in a forest fragment near a rural community with reports of human Chagas disease. T. cruzi infection was diagnosed by blood smear examinations, blood culture, scent glands secretion culture, histopathological examination, and nested-PCR. Positive samples were subjected to PCR to characterize the discrete typing units (DTUs) of T. cruzi. Characteristic trypomastigotes of T. cruzi were observed in the blood smear, and spheromastigotes, epimastigotes, and trypomastigotes were visualized in the cultures. Non-suppurative myocarditis associated with amastigote clusters was the principal histopathological finding. DNA from T. cruzi was detected in samples of blood, blood cultures, scent glands secretion cultures, cardiac muscles, and the spleen. The TcI and the TcII/V/VI group DTUs were detected in blood culture and scent glands secretion cultures. Infection by T. cruzi can cause myocarditis in P. opossum and DTUs TcI and TcII/V/VI group mixed infection can be detected in the acute phase. P. opossum can be a source of infection for triatomine vectors and has the potential source for direct transmission of T. cruzi by secretions from the scent glands. These data are important to improve the understanding of the complex enzootic transmission cycle of T. cruzi in the Brazilian Amazon.
Subject(s)
Chagas Disease/veterinary , Opossums , Trypanosoma cruzi/isolation & purification , Animals , Chagas Disease/parasitology , Chagas Disease/pathology , Heart/parasitology , Male , Myocardium/pathology , Scent Glands/parasitology , Scent Glands/pathologyABSTRACT
ABSTRACT: The present study aimed to diagnose the natural infection of captive and free-living procyonids with Trypanosoma evansi in the states of Amapá and Pará, Brazil. From February 2012 to August 2013, whole blood samples and blood smears were obtained from 45 free-living procyonids and from nine procyonids kept in captivity in wild life refuges and zoobotanical parks in the states of Amapá and Pará. Whole blood samples were collected and kept at -20ºC for the detection of T. evansi DNA by PCR using the RoTat 1.2 forward and RoTat 1.2 reverse primers. In addition, the blood smears were processed and examined for the presence of trypomastigote forms of T. evansi. T. evansi DNA was detected in 18.52% (10/54) of the procyonids, namely, in captive crab-eating raccoons and captive and free-living coatis in Pará State. No trypomastigote forms were observed in the blood smears. DNA from T. evansi was detected in P. cancrivorus and N. nasua in Pará State, being this the first such report in P. cancrivorus.
RESUMO: O objetivo do presente trabalho foi realizar o diagnóstico da infecção natural por Trypanosoma evansi em procionídeos de vida livre e de cativeiro dos estados do Amapá e Pará, Brasil. Durante o período de fevereiro de 2012 a agosto de 2013, amostras de sangue total e esfregaços sanguíneos foram obtidos de 45 procionídeos de vida livre e de nove mantidos em cativeiro em mantenedores e Parques Zoobotânicos dos estados do Amapá e Pará. As amostras de sangue total foram coletadas e mantidas a -20ºC para pesquisa de DNA de T. evansi pela PCR utilizando-se os iniciadores RoTat 1.2 forward e RoTat 1.2 reverse. Os esfregaços sanguíneos também foram processados e examinados para a pesquisa de formas tripomastigotas do agente. DNA de T. evansi foi detectado em 18,52% (10/54) dos procionídeos, ocorrendo em mãos-peladas de cativeiro e quatis de vida livre e de cativeiro no estado do Pará. Não foram observadas formas tripomastigotas nos esfregaços sanguíneos. DNA de T. evansi foi detectado em P. cancrivorus e N. nasua no estado do Pará, sendo este o primeiro relato em P. cancrivorus.
