Hilpertshauser, Heidi Deplazes, Peter Schnyder, Manuela Gern, Lise Mathis, Alexander <jats:title>ABSTRACT</jats:title> <jats:p>Concurrent infections with vector-borne pathogens affected a cattle herd in Switzerland, and one of the pathogens was identified as <jats:italic>Babesia bigemina</jats:italic>, which had never been observed in this country before. Therefore, a survey of the occurrence of ruminant <jats:italic>Babesia</jats:italic> spp. and their tick vectors in Switzerland was conducted. A total of 2,017 ticks were collected from sheep, goats, cattle, and wild ruminants (deer, roe deer, and chamois) in southern parts of Switzerland and identified morphologically. The vast majority of the ticks (99.2%) were <jats:italic>Ixodes ricinus</jats:italic>, but 14 ticks from sheep and goats were identified as <jats:italic>Dermacentor marginatus</jats:italic> and two ticks from wild ruminants were identified as <jats:italic>Hemaphysalis punctata</jats:italic>. PCR analyses of 700 ticks revealed the presence of <jats:italic>Babesia divergens</jats:italic> (<jats:italic>n</jats:italic> = 6), <jats:italic>Babesia</jats:italic> sp. genotype EU1 (<jats:italic>n</jats:italic> = 14), and <jats:italic>B. major</jats:italic> (<jats:italic>n</jats:italic> = 2), whose suggested occurrence was confirmed in this study by molecular analysis, and the presence of novel <jats:italic>Babesia</jats:italic> sp. genotype CH1 (<jats:italic>n</jats:italic> = 4), which is closely related to <jats:italic>B. odocoilei</jats:italic> and to <jats:italic>Babesia</jats:italic> sp. genotype RD61 reported from North America. The identification of <jats:italic>B. divergens</jats:italic> and <jats:italic>B. major</jats:italic> in ticks collected from wild ruminants cast doubt on the postulated strict host specificity of these bovine <jats:italic>Babesia</jats:italic> species. Furthermore, the zoonotic <jats:italic>Babesia</jats:italic> sp. genotype EU1 was detected in ticks collected from domestic animals but was obtained predominantly from ticks collected from wild ruminants. More than one tick containing DNA of different <jats:italic>Babesia</jats:italic> spp. were collected from two red deer. Hence, the role of these game animals as reservoir hosts of <jats:italic>Babesia</jats:italic> spp. seems to be important but requires further investigation.</jats:p> application/pdf https://sonar.ch/global/documents/235919 eng info:eu-repo/semantics/altIdentifier/doi/10.1128/aem.00823-06 info:eu-repo/semantics/altIdentifier/issn/0099-2240 info:eu-repo/semantics/openAccess Applied and Environmental Microbiology. - American Society for Microbiology. - 2006, vol. 72, no. 10, p. 6503-6507 Biotechnology Food Science Ecology Applied Microbiology and Biotechnology Babesia spp. Identified by PCR in Ticks Collected from Domestic and Wild Ruminants in Southern Switzerland http://purl.org/coar/resource_type/c_6501