Institute of Animal Hygiene and Veterinary Public Health, Faculty of Veterinary Medicine, University of Leipzig, D-04103 Leipzig, Germany.
Bundeswehr Institute of Microbiology, Munich, Germany.
Ticks Tick Borne Dis. 2020 Nov;11(6):101543. doi: 10.1016/j.ttbdis.2020.101543. Epub 2020 Aug 24.
It is commonly assumed that Dermacentor reticulatus immature life stages are nidicolous and therefore cannot be collected from vegetation. However, in June and July of 2018 and 2019, a total of 47 questing D. reticulatus larvae and two nymphs were collected by the flagging method in two different sites close to the city of Leipzig, Germany. To confirm their role in the transmission of tick-borne pathogens, 45 larvae (pooled by 2 in 21 pools and 1 pool with three individuals) and one nymph were tested either by conventional or real-time PCR for the presence of Bartonella spp., Neoehrlichia mikurensis, Rickettsia spp., and Babesia spp. All samples tested negative for Bartonella spp., N. mikurensis, and Babesia spp.; while the minimal infection rate of larvae for Rickettsia spp. was 42%, and the one tested nymph was also positive. Sequencing partial ompB genes revealed the presence of Rickettsia raoultii in larvae and nymph. Further research needs to be done to determine under which circumstances immature D. reticulatus ticks are found outside the burrows of their hosts and can be collected from vegetation.
人们通常认为 Dermacentor reticulatus 的幼虫期是巢栖的，因此不能从植被中收集。然而，在 2018 年和 2019 年 6 月至 7 月，在德国莱比锡市附近的两个不同地点，通过标记法共收集到 47 只游离的 Dermacentor reticulatus 幼虫和 2 只若虫。为了确认它们在传播蜱传病原体中的作用，对 45 只幼虫（每 2 只幼虫合并为 1 个样本，共 21 个样本，3 只幼虫为 1 个样本）和 1 只若虫进行了常规或实时 PCR 检测，以检测是否存在巴尔通体属、新立克次体、立克次体属和巴贝斯虫属。所有样本均未检测到巴尔通体属、新立克次体和巴贝斯虫属；而幼虫的立克次体属最小感染率为 42%，检测到的 1 只若虫也呈阳性。对部分 ompB 基因的测序显示，幼虫和若虫中存在拉乌尔氏菌。需要进一步研究以确定 Dermacentor reticulatus 的幼虫在何种情况下会离开宿主的巢穴并出现在植被中，以便于收集。
