Laboratório de Biologia de Tripanosomatídeos, Instituto Oswaldo Cruz/FIOCRUZ, Av. Brasil 4365, Rio de Janeiro, RJ, CEP. 21040-360, Brazil.
Parasit Vectors. 2018 Sep 6;11(1):502. doi: 10.1186/s13071-018-3067-2.
Trypanosoma cruzi (Kinetoplastea: Trypanosomatidae) infects all tissues of its hosts, which along with humans, include hundreds of mammalian species in the Americas. The epidemiology of T. cruzi has been changing in that currently the majority of the cases and/or outbreaks of Chagas disease occur by the ingestion of comestibles contaminated by T. cruzi metacyclic forms. These cases/outbreaks occur in distinct regional scenarios, mainly in the Amazon biome and are related to the local interaction mode of humans with their surroundings, as well as with the overall local ecological peculiarities. As trypanosomiasis caused by T. cruzi is primarily a zoonosis, understanding the variables that influences its transmission in the wild as well as the role played by the extant fauna in the maintenance of the parasite, is critical in establishing control measures. Here, we present the results of our studies of T. cruzi infection of free ranging wild mammalian fauna in the five biomes of Brazil, a country of continental dimensions. From 1992 up to 2017, we examined a total of 6587 free-ranging non-volant wild mammal specimens. Our studies found that 17% of mammals were seropositive and 8% of all animals displayed positive hemocultures indicative of high parasitemia and, consequently, of infectivity potential. We observed that opossums, mainly Philander spp. and Didelphis spp., the coati Nasua nasua, the capuchin monkey Sapajus libidinosus and the golden lion tamarin Leontopithecus rosalia, were mammal taxa that demonstrated higher rates of positive hemocultures. Additionally, Didelphis spp. demonstrated to be a competent bioaccumulator of TcI diversity. Chiroptera were distinguished for hosting the greatest diversity of species and genotypes of Trypanosoma spp. Additionally the observation of the higher host range of some Trypanosoma spp., shows the need to reassess the ecology of representatives of the taxon. Altogether, our results showed that each locality, may display distinct enzootiological and epidemiological scenarios that must be taken into account when it comes to establishing control and/or clarification campaigns of the local population.
克氏锥虫（动基体目：锥虫科）感染其宿主的所有组织，这些宿主包括美洲数百种哺乳动物物种，包括人类。克氏锥虫的流行病学一直在变化，目前大多数恰加斯病病例和/或暴发是由于摄入被克氏锥虫循环形态污染的食物而发生的。这些病例/暴发发生在不同的区域情景中，主要在亚马逊生物群落，与人类与其周围环境以及当地整体生态特征的局部相互作用模式有关。由于克氏锥虫引起的锥虫病主要是一种人畜共患病，因此了解影响其在野外传播的变量以及现存动物群在维持寄生虫方面所起的作用，对于制定控制措施至关重要。在这里，我们介绍了我们在巴西五个生物群落中对自由放养的野生哺乳动物区系中克氏锥虫感染的研究结果，巴西是一个拥有广阔大陆的国家。从 1992 年到 2017 年，我们共检查了 6587 只自由放养的非飞行野生哺乳动物标本。我们的研究发现，17%的哺乳动物呈血清阳性，8%的动物显示出阳性血培养，表明存在高寄生虫血症和潜在的感染性。我们观察到负鼠，主要是宽吻负鼠和白足负鼠，浣熊 Nasua nasua，绒猴 Sapajus libidinosus 和金狮面狨 Leontopithecus rosalia，是表现出更高阳性血培养率的哺乳动物类群。此外，白足负鼠表现出对 TcI 多样性的高生物蓄积能力。蝙蝠科因其宿主的物种和基因型多样性而引人注目。此外，观察到一些锥虫属物种的宿主范围较高，表明需要重新评估该分类群代表的生态学。总的来说，我们的研究结果表明，每个地区都可能显示出不同的地方病和流行病学情况，在制定针对当地人口的控制和/或澄清运动时必须考虑到这些情况。
