Anses, Rabies and Wildlife Laboratory, National Reference Laboratory for Echinococcus spp., Malzéville, France.
Anses, Rabies and Wildlife Laboratory, National Reference Laboratory for Echinococcus spp., Malzéville, France.
Vet Parasitol Reg Stud Reports. 2022 May;30:100724. doi: 10.1016/j.vprsr.2022.100724. Epub 2022 Mar 24.
Alveolar echinococcosis is a severe, potentially fatal, parasitic disease caused by ingestion of microscopic eggs of Echinococcus multilocularis. The lifecycle of the parasite is essentially sylvatic, and based on a prey-predator relationship between red foxes and small rodents. A westward expansion from the eastern historical focus has been reported in France, though the parasite has also been detected in the southern Alps. While the focus in the Auvergne region (central France) was described in the 1980s, the southern delimitation of the actual endemic area, especially in the south, was unknown in the absence of dedicated surveys. Red fox samples were collected from 2013 to 2020 in the framework of other transversal epidemiological studies in five sampling areas from southwestern and southeastern France. One hundred and seven intestines were analysed by SSCT, and 221 faecal samples from intestines were analysed by copro-qPCR. None of the 328 foxes exhibited E. multilocularis worms or DNA. Although the presence of E. multilocularis cannot be totally excluded in the departments from the study areas, the sample size tested argues for an absence of the parasite in these studied areas, which is in accordance with the currently known endemic situation in France. These new data are helpful in determining the southernmost limit of E. multilocularis distribution in France. The warm, dry Mediterranean climate in the southeastern areas is less favourable to the transmission of E. multilocularis and especially to the survival of eggs in the environment than the climate in the French Alps or Liguria (Italy) climate where the parasite is present. The intermediate area between the southwestern study areas and the historical focus of Auvergne, which is separated by around 150 km, will be investigated in the coming years. Moreover, an ongoing national surveillance programme on E. multilocularis in foxes is targeting French departements along the edge of the known endemic area both in the southeast and southwest. The data produced will supplement the results of this study, thus greatly helping to define the current distribution of E. multilocularis in France and to target prevention measures to reduce human exposure.
泡型包虫病是一种严重的、潜在致命的寄生虫病,由吞食细粒棘球绦虫的微小虫卵引起。该寄生虫的生命周期基本是森林型的,基于红狐和小型啮齿动物之间的猎物-捕食者关系。虽然在法国东部的历史疫区报告了一种向西扩张的趋势,但寄生虫也在阿尔卑斯山南麓被发现。虽然在奥弗涅地区(法国中部)的焦点在 20 世纪 80 年代就有描述,但在没有专门调查的情况下,实际流行地区,特别是南部地区的南部边界是未知的。2013 年至 2020 年,在法国西南部和东南部五个采样区进行的其他横向流行病学研究框架内,收集了红狐样本。107 个肠段通过 SSCT 进行了分析,221 个来自肠段的粪便样本通过 copro-qPCR 进行了分析。328 只狐狸中均未发现细粒棘球绦虫的成虫或 DNA。尽管在研究区域的部门中不能完全排除细粒棘球绦虫的存在,但测试的样本量表明这些研究区域中没有寄生虫,这与法国目前已知的流行情况一致。这些新数据有助于确定法国细粒棘球蚴分布的最南端界限。东南部温暖干燥的地中海气候对细粒棘球绦虫的传播,特别是对环境中虫卵的生存,不如法国阿尔卑斯山或意大利利古里亚(Liguria)(寄生虫存在的地方)的气候有利。未来几年将调查西南部研究区和奥弗涅历史疫区之间的中间区域,中间区相距约 150 公里。此外,一项针对狐狸中细粒棘球绦虫的全国监测计划正在法国东南部和西南部已知流行区边缘的法国部门进行。所产生的数据将补充本研究的结果,从而极大地有助于确定法国细粒棘球蚴的当前分布,并针对减少人类接触的预防措施。