Resource Ecology Group, Wageningen University, Wageningen, the Netherlands.
Present address: Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Skogsmarksgränd 17, 907 36, Umeå, Sweden.
Parasit Vectors. 2018 Nov 20;11(1):600. doi: 10.1186/s13071-018-3126-8.
Elucidating which wildlife species significantly contribute to the maintenance of Ixodes ricinus populations and the enzootic cycles of the pathogens they transmit is imperative in understanding the driving forces behind the emergence of tick-borne diseases. Here, we aimed to quantify the relative contribution of four mustelid species in the life-cycles of I. ricinus and Borrelia burgdorferi (sensu lato) in forested areas and to investigate their role in the transmission of other tick-borne pathogens. Road-killed badgers, pine martens, stone martens and polecats were collected in Belgium and the Netherlands. Their organs and feeding ticks were tested for the presence of tick-borne pathogens.
Ixodes hexagonus and I. ricinus were found on half of the screened animals (n = 637). Pine martens had the highest I. ricinus burden, whereas polecats had the highest I. hexagonus burden. We detected DNA from B. burgdorferi (s.l.) and Anaplasma phagocytophilum in organs of all four mustelid species (n = 789), and Neoehrlichia mikurensis DNA was detected in all species, except badgers. DNA from B. miyamotoi was not detected in any of the investigated mustelids. From the 15 larvae of I. ricinus feeding on pine martens (n = 44), only one was positive for B. miyamotoi DNA, and all tested negative for B. burgdorferi (s.l.), N. mikurensis and A. phagocytophilum. The two feeding larvae from the investigated polecats (n = 364) and stone martens (n = 39) were negative for all four pathogens. The infection rate of N. mikurensis was higher in feeding nymphs collected from mustelids compared to questing nymphs, but not for B. burgdorferi (s.l.), B. miyamotoi or A. phagocytophilum.
Although all stages of I. ricinus can be found on badgers, polecats, pine and stone martens, their relative contribution to the life-cycle of I. ricinus in forested areas is less than 1%. Consequently, the relative contribution of mustelids to the enzootic cycles of I. ricinus-borne pathogens is negligible, despite the presence of these pathogens in organs and feeding ticks. Interestingly, all four mustelid species carried all stages of I. hexagonus, potentially maintaining enzootic cycles of this tick species apart from the cycle involving hedgehogs as main host species.
阐明哪些野生动物物种对维持硬蜱种群和传播其病原体的地方性循环有重要贡献，对于理解蜱传疾病出现的驱动因素至关重要。在这里，我们旨在量化四种貂属物种在硬蜱和伯氏疏螺旋体（广义）的生活史中的相对贡献，并研究它们在传播其他蜱传病原体中的作用。在比利时和荷兰，收集了被车撞死的獾、松貂、石貂和伶鼬。检测它们的器官和取食的蜱是否存在蜱传病原体。
在被筛查的 637 只动物中，有一半（n=637）发现了硬蜱和六角形硬蜱。松貂的硬蜱负担最高，而伶鼬的六角形硬蜱负担最高。我们在四种貂属物种的所有器官中都检测到了伯氏疏螺旋体（广义）和嗜吞噬细胞无形体的 DNA（n=789），除了獾外，所有物种都检测到了新立克次体的 DNA。在调查的貂属动物中，均未检测到伯氏疏螺旋体 miyamotoi 的 DNA。从取食松貂的 15 只硬蜱幼虫（n=44）中，只有一只幼虫的伯氏疏螺旋体 miyamotoi DNA 检测呈阳性，所有幼虫均对伯氏疏螺旋体（广义）、新立克次体和嗜吞噬细胞无形体检测呈阴性。从调查的伶鼬（n=364）和石貂（n=39）的 2 只取食幼虫中，所有幼虫均对这四种病原体检测呈阴性。与在野外的幼虫相比，从貂属动物收集的取食若虫的新立克次体感染率更高，但伯氏疏螺旋体（广义）、伯氏疏螺旋体 miyamotoi 或嗜吞噬细胞无形体的感染率则没有差异。
尽管獾、伶鼬、松貂和石貂都可以找到硬蜱的所有阶段，但它们对森林地区硬蜱生活史的相对贡献小于 1%。因此，尽管貂属动物的器官和取食的蜱中存在这些病原体，但它们对硬蜱传播病原体的地方性循环的贡献可以忽略不计。有趣的是，所有四种貂属物种都携带了硬蜱的所有阶段，除了以刺猬为主宿主的循环外，还有可能维持着这种蜱的地方性循环。
