Population genetic analysis of Chadian Guinea worms reveals that human and non-human hosts share common parasite populations

Following almost 10 years of no reported cases, Guinea worm disease (GWD or dracunculiasis) reemerged in Chad in 2010 with peculiar epidemiological patterns and unprecedented prevalence of infection among non-human hosts, particularly domestic dogs. Since 2014, animal infections with Guinea worms have also been observed in the other three countries with endemic transmission (Ethiopia, Mali, and South Sudan), causing concern and generating interest in the parasites’ true taxonomic identity and population genetics. We present the first extensive population genetic data for Guinea worm, investigating mitochondrial and microsatellite variation in adult female worms from both human and non-human hosts in the four endemic countries to elucidate the origins of Chad’s current outbreak and possible host-specific differences between parasites. Genetic diversity of Chadian Guinea worms was considerably higher than that of the other three countries, even after controlling for sample size through ra...在近10年无官方报告病例之后，几内亚线虫病（Guinea worm disease，简称GWD；龙线虫病dracunculiasis）于2010年在乍得再度暴发，呈现出特殊的流行病学特征，且非人宿主（尤其是家犬）的感染率达到前所未有的水平。自2014年起，其余3个存在地方性传播的国家（埃塞俄比亚、马里、南苏丹）也陆续发现动物感染几内亚线虫的病例，这引发了学界的广泛担忧与研究兴趣，相关研究聚焦于该寄生虫的真实分类学身份与群体遗传学特性。本研究首次提供了几内亚线虫的大规模群体遗传学数据，针对上述4个流行国家中来源于人类与非人宿主的成年雌虫，分析其线粒体与微卫星变异情况，以厘清乍得当前暴发疫情的源头，以及寄生虫是否存在宿主特异性差异。即便通过抽样量校正（原文未完成：through ra...），乍得几内亚线虫的遗传多样性仍显著高于其余3个国家的线虫种群。