Estrada-Peña Agustin, Sprong Hein, Wijburg Sara R
Department of Animal Health, University of Zaragoza, Spain.
Instituto Agroalimentario de Aragón, IA2, 50013-Zaragoza, Spain.
Curr Res Parasitol Vector Borne Dis. 2024 Jun 29;6:100198. doi: 10.1016/j.crpvbd.2024.100198. eCollection 2024.
The tick parasitizes a wide range of vertebrates. These hosts vary in the relative contribution to the feeding of the different tick life stages, and their interplay is pivotal in the transmission dynamics of tick-borne pathogens. We aimed to know if there is a phylogenetic signal in the feeding and propagation hosts of , independently of other traits, as well as in the amplification of () in feeding larvae. We used a compilation of 1127 published field surveys in Europe, providing data for 96,586 hosts, resulting in 265,124 larvae, 72,080 nymphs and 37,726 adults. The load of immature ticks on hosts showed a significant phylogenetic signal towards the genera , and (nymphs only). We hypothesize that such signal is the background hallmark of the primitive hosts associations of , probably in the glaciation refugia. A secondary phylogenetic signal for tick immatures appeared for some genera of Rodentia and Eulipotyphla. Results suggest the notion that the tick gained these hosts after spread from glaciation refugia. Analyses support a phylogenetic signal in the tick adults, firmly linked to Cetartiodactyla, but not to Carnivora or Aves. This study provides the first demonstration of host preferences in the generalist tick . We further demonstrate that combinations of vertebrates contribute in different proportions supporting the tick life-cycle in biogeographical regions of the Western Palaearctic as each region has unique combinations of dominant hosts. Analysis of the amplification of () demonstrated that each genospecies is better amplified by competent reservoirs with which a strong phylogenetic signal exists. These vertebrates are the same along the spatial range: environmental traits do not change the reservoirs along the large territory studied. The transmission of () is amplified by a few species of vertebrates, that share biogeographical regions with the tick vector in variable proportions.
蜱虫寄生于多种脊椎动物。这些宿主对蜱虫不同生命阶段取食的相对贡献各不相同，它们之间的相互作用在蜱传病原体的传播动态中起着关键作用。我们旨在了解，在不考虑其他特征的情况下，蜱虫的取食和繁殖宿主中是否存在系统发育信号，以及在取食幼虫中伯氏疏螺旋体（Borrelia burgdorferi）的增殖情况中是否存在系统发育信号。我们使用了欧洲1127项已发表的实地调查汇编数据，这些数据涵盖了96586个宿主，共产生了265124只幼虫、72080只若虫和37726只成虫。宿主上未成熟蜱虫的负载量对硬蜱属（Ixodes）、篦子硬蜱属（Ixodes ricinus）以及全沟硬蜱（Ixodes persulcatus）（仅针对若虫）显示出显著的系统发育信号。我们推测，这种信号是蜱虫与原始宿主关联的背景标志，可能出现在冰川避难所中。啮齿目（Rodentia）和真盲缺目（Eulipotyphla）的一些属出现了蜱虫未成熟阶段的二级系统发育信号。结果表明，蜱虫是从冰川避难所扩散后才获得这些宿主的。分析支持蜱虫成虫中存在系统发育信号，且该信号与鲸偶蹄目（Cetartiodactyla）紧密相关，但与食肉目（Carnivora）或鸟类（Aves）无关。这项研究首次证明了广食性蜱虫（Ixodes ricinus）存在宿主偏好。我们进一步证明，脊椎动物的组合在不同比例上支持了西古北区生物地理区域内蜱虫的生命周期，因为每个区域都有独特的优势宿主组合。对伯氏疏螺旋体（Borrelia burgdorferi）增殖情况的分析表明，每个基因种都能被与其存在强烈系统发育信号的适宜宿主更好地增殖。在整个空间范围内，这些脊椎动物是相同的：在所研究的广大区域内，环境特征并未改变宿主。伯氏疏螺旋体（Borrelia burgdorferi）的传播由少数几种脊椎动物增强，这些脊椎动物与蜱虫媒介在不同比例上共享生物地理区域。
