Dept. of Biology, University of Oslo, P.O. Box 1050 Blindern, N-0316 Oslo, Norway.
Ticks Tick Borne Dis. 2011 Mar;2(1):37-43. doi: 10.1016/j.ttbdis.2010.10.004. Epub 2010 Nov 26.
Birds are capable of transporting ticks and, consequently, tick-borne pathogens over long distances and across geographical barriers such as oceans and deserts. The purpose of this study was to assess the prevalence of Borrelia spp. in ticks transported by birds by using PCR. A total of 9768 northward-migrating passerine birds was examined for ticks at 4 bird observatories along the southern Norwegian coast during their spring migration in 2003-2005. Two of the bird observatories were located on islands where flagging revealed very few or no ticks (Akerøya and Store Færder), while the other 2 were located in areas with established dense tick populations: an island, Jomfruland (>100 ticks per hour of flagging) and a mainland locality, Lista (40 ticks in one hour of flagging). Borrelia spp. were found in 70 (13.6%) of 513 examined Ixodes ricinus nymphs (19 B. afzelii, 38 B. garinii, two B. turdi, and 11 B. valaisiana) and in 14 (8.1%) of 172 examined I. ricinus larvae (ten B. garinii, one B. turdi, and three B. valaisiana). This report is the first to identify B. turdi in Europe. Ticks collected from birds of the genus Turdus (T. merula, T. philomelos, and T. iliacus) had a higher prevalence of Borrelia spp. than ticks from the other passerine genera. Ticks that were cofeeding with a Borrelia-infected tick had an increased probability of being infected with the same Borrelia species. Ticks collected on birds from the south-western locality Lista were less likely to have Borrelia than ticks found on birds from the other, more eastern localities. The Turdus spp. are particularly important, both because they carry many ticks per bird and because ticks carried by these species have a higher prevalence of Borrelia. This higher prevalence may be related to Borrelia infection of the birds or transmission of Borrelia through cofeeding. The prevalence of the different Borrelia species in ticks collected from migratory birds may be related to migration routes.
鸟类能够携带蜱虫，并因此在长途和地理障碍（如海洋和沙漠）上传播蜱传病原体。本研究旨在使用 PCR 评估通过鸟类传播的蜱虫中伯氏疏螺旋体的流行率。在 2003 年至 2005 年期间，在挪威南部沿海的 4 个鸟类观测站，对 9768 只北移的雀形目鸟类进行了蜱虫检查。其中两个鸟类观测站位于 flagged 发现蜱虫极少或没有的岛屿上（Akerøya 和 Store Færder），而其他两个位于 established 密集蜱虫种群的地区：一个岛屿 Jomfruland（每小时 flagging 有超过 100 只蜱虫）和一个大陆地点 Lista（每小时 flagging 有 40 只蜱虫）。在 513 只检查的硬蜱若虫中发现了 70 只（13.6%）伯氏疏螺旋体（19 只 B. afzelii、38 只 B. garinii、2 只 B. turdi 和 11 只 B. valaisiana），在 172 只检查的硬蜱幼虫中发现了 14 只（8.1%）伯氏疏螺旋体（10 只 B. garinii、1 只 B. turdi 和 3 只 B. valaisiana）。这是首次在欧洲发现 B. turdi。从 Turdus 属（T. merula、T. philomelos 和 T. iliacus）鸟类收集的蜱虫的 Borrelia spp. 患病率高于其他雀形目属的蜱虫。与感染 Borrelia 的蜱虫共同进食的蜱虫感染同一 Borrelia 物种的可能性增加。从西南部 Lista 地点收集的鸟类携带的蜱虫携带 Borrelia 的可能性低于从其他更东部地点收集的鸟类携带的蜱虫。Turdus spp. 尤为重要，因为它们每只鸟携带的蜱虫数量较多，而且这些物种携带的蜱虫 Borrelia 感染率较高。这种更高的患病率可能与鸟类的 Borrelia 感染或通过共同进食传播 Borrelia 有关。从候鸟身上采集的蜱虫中不同 Borrelia 物种的流行率可能与迁徙路线有关。
