Laboratory of Animal Parasitology, Graduate Program in Animal Health in the Amazon, Institute of Veterinary Medicine, Federal University of Pará, Castanhal, Pará, Brazil.
Laboratory of Animal Pathology, Graduate Program in Animal Health in the Amazon, Institute of Veterinary Medicine, Federal University of Pará, Castanhal, Pará, Brazil.
Vet Parasitol Reg Stud Reports. 2020 Dec;22:100463. doi: 10.1016/j.vprsr.2020.100463. Epub 2020 Sep 8.
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.
克氏锥虫是美洲锥虫病的病原体，可感染人类和不同种类的家养和野生动物。有袋动物是克氏锥虫的重要野生动物宿主，有助于维持该病原体在森林和半野外环境中的存在。本研究的目的是报告在一只源自巴西亚马逊的袋狸中发生的克氏锥虫自然感染的寄生虫学和临床病理学发现。该动物是在一个有人类恰加斯病报告的农村社区附近的森林碎片中捕获的。通过血涂片检查、血液培养、气味腺分泌物培养、组织病理学检查和巢式 PCR 诊断克氏锥虫感染。阳性样本进行 PCR 以鉴定克氏锥虫的离散型单位 (DTU)。在血涂片上观察到克氏锥虫的典型锥虫，在培养物中观察到球形鞭毛体、上皮鞭毛体和锥虫。与阿米巴聚集相关的非化脓性心肌炎是主要的组织病理学发现。在血液、血液培养物、气味腺分泌物培养物、心肌和脾脏样本中均检测到克氏锥虫 DNA。在血液培养物和气味腺分泌物培养物中检测到 TcI 和 TcII/V/VI 组 DTU。克氏锥虫感染可导致袋狸心肌炎，在急性期可检测到 TcI 和 TcII/V/VI 组混合感染。袋狸可能是三锥虫媒介的感染源，并具有通过气味腺分泌物直接传播克氏锥虫的潜在来源。这些数据对于提高对巴西亚马逊地区克氏锥虫复杂地方性传播周期的理解很重要。
