Untersuchungen zur Häufigkeit von Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum and Babesia spp. in Ixodes ricinus aus Bayern und Baden-Württemberg

摘要

625 adult unfed I. ricinus ticks from three recreational areas located near Munich and Passau, 275 adult engorged I. ricinus ticks from dogs of Bavaria and Baden-Württemberg and 25 adult engorged I. ricinus ticks from cattle of an area in Switzerland, which is endemic for bovine granulocytic ehrlichiosis, were collected over a specific period (3/2003-3/2004). The ticks were examined for an infection with B. burgdorferi sensu lato spp., A. phagocytophilum and piroplasms by the use of Real-Time PCR and nested PCR. In addition RFLP analysis and sequencing were chosen for the differentiation of the species and OspA types of B. burgdorferi sensu lato.The examination of unfed ticks resulted in a prevalence of 35,4% for B. burgdorferi sensu lato, 4,5% for A. phagocytophilum and 1,3% for piroplasms. There was no significant difference for the infection rates of B. burgdorferi sensu lato between the different sampling areas, whereas A. phagocytophilum showed a significantly higher prevalence in one sampling side in Munich and a significantly lower prevalence in Passau. Apart from infections with only one pathogen, coinfections with B. burgdorferi sensu lato and A. phagocytophilum could be detected in 1,1% of the unfed ticks, with a local cluster in one area in Munich and 0,3% of the unfed ticks showed a coinfection with B. burgdorferi sensu lato and piroplasms.Prevalence rates of 8,4%, 4,7% and 5,1% were identified for B. burgdorferi sensu lato, A. phagocytophilum and piroplasms respectively in engorged ticks from dogs, 0,7% of these ticks were coinfected with B. burgdorferi sensu lato and A. phagocytophilum.The examination of engorged ticks from cattle revealed in a prevalence rate of 8,0% for B. burgdorferi sensu lato and 60,0% for A. phagocytophilum. The high infection rate of A. phagocytophilum probably resulted from an infection of the cattle with this pathogen.The difference in the prevalence rate of B. burgdorferi sensu lato in unfed and engorged ticks might be caused by their distinct geographical origin, the degree of blood uptake and different factors in the blood of the different host species which are able to protect the host from being infected with Borrelia.The differentiation of B. burgdorferi sensu lato into the species and OspA types showed that the clinically relevant species B. afzelii, B. burgdorferi sensu stricto and B. garinii, in which B. garinii was represented by the OspA types 3, 4, 5, 6 and 8 could be detected. Additionally, B. valaisiana, a species which is suspected of being pathogenic to humans and the recently described new Borrelia genospecies, B. spielmanii (previously A14S), were detected. Alltogether a broad heterogeneity for Borrelia species and subspecies (classified by OspA types) could be observed in unfed ticks, above all in one sampling side in Munich. Ticks engorgd from dogs and cattle showed a less heterogeneous pattern of distribution.