Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, SK, S7N 5B4, Canada.
Research Group on Epidemiology of Zoonoses and Public Health (GREZOSP), Faculty of Veterinary Medicine, Université de Montréal, Saint-Hyacinthe, QC, J2S 2M2, Canada.
Sci Rep. 2024 Feb 2;14(1):2812. doi: 10.1038/s41598-024-53369-6.
Predators in food webs are valuable sentinel species for zoonotic and multi-host pathogens such as Toxoplasma gondii. This protozoan parasite is ubiquitous in warm-blooded vertebrates, and can have serious adverse effects in immunocompromised hosts and foetuses. In northern ecosystems, T. gondii is disproportionately prevalent in Inuit people and wildlife, in part due to multiple routes of transmission. We combined data on T. gondii infection in foxes from Nunavik (northern Québec, Canada) with stable isotope data tracking trophic relationships between foxes and several of their main prey species. Red (Vulpes vulpes) and Arctic fox (Vulpes lagopus) carcasses were collected by local trappers from 2015 to 2019. We used magnetic capture PCR to detect DNA of T. gondii in heart and brain tissues, and enzyme-linked immunosorbent assay to detect antibodies in blood. By linking infection status with diet composition, we showed that infected foxes had a higher probability of consuming aquatic prey and migratory geese, suggesting that these may be important sources of T. gondii transmission in the Arctic. This use of stable isotopes to reveal parasite transmission pathways can be applied more broadly to other foodborne pathogens, and provides evidence to assess and mitigate potential human and animal health risks associated with T. gondii in northern ecosystems.
在食物网中，掠食者是像刚地弓形虫这样的人畜共患病和多宿主病原体的有价值的哨兵物种。这种原生动物寄生虫广泛存在于温血脊椎动物中，在免疫功能低下的宿主和胎儿中可能会产生严重的不良影响。在北方生态系统中，刚地弓形虫在因纽特人和野生动物中不成比例地流行，部分原因是有多种传播途径。我们将来自努纳武特（加拿大魁北克省北部）的狐狸感染刚地弓形虫的数据与稳定同位素数据相结合，这些数据跟踪了狐狸与其几种主要猎物之间的营养关系。2015 年至 2019 年，当地的猎人收集了红狐（Vulpes vulpes）和北极狐（Vulpes lagopus）的尸体。我们使用磁捕获 PCR 检测心脏和脑组织中的刚地弓形虫 DNA，并用酶联免疫吸附测定法检测血液中的抗体。通过将感染状况与饮食成分联系起来，我们发现感染的狐狸更有可能食用水生猎物和迁徙的鹅，这表明这些可能是北极地区刚地弓形虫传播的重要来源。这种利用稳定同位素揭示寄生虫传播途径的方法可以更广泛地应用于其他食源性病原体，并提供证据来评估和减轻与北方生态系统中刚地弓形虫相关的潜在人类和动物健康风险。
