title: Ixodes ricinus and Borrelia prevalence at the Arctic Circle in Norway.
abstract: The distribution limit of Ixodes ricinus ticks in northwestern Europe (Brønnøy, Norway, 1° south of the Arctic Circle), has been known since the 1930s. To reconfirm this finding and extend studies in the areas adjacent to the Arctic Circle (66°33' N), ticks were collected from dogs and cats in 8 districts in northern Norway from 64°56' N to 68°48' N. We detected 549 I. ricinus, 244 (44%) of them in Brønnøy district, and 305 (range 6-87 ticks) in 7 districts in the northern part of the study area. The prevalence of Borrelia in these ticks was determined by real-time PCR. In the Brønnøy district (65°28' N, 12°12' E), 29% of the I. ricinus were Borrelia spp.-positive, and the species B. afzelii was nearly twice as prevalent as B. garinii and/or B. valaisiana. In the study area north of Brønnøy district, only 12 (4%) of the collected ticks contained Borrelia spp. In conclusion, tick occurrence and Borrelia prevalence are high in the Brønnøy district. In contrast, I. ricinus occurrence and Borrelia prevalence are low further north across the Arctic Circle in Norway.
authors.affiliation: Department of Microbiology and Infection Control, University Hospital of North Norway, Tromsø, Norway. Electronic address: dag.hvidsten@unn.no.
authors.forename: Dag
authors.initials: D
authors.lastname: Hvidsten
authors.affiliation: Department of Production Animal Clinical Sciences, Norwegian School of Veterinary Science, Sandnes, Norway.
authors.forename: Snorre
authors.initials: S
authors.lastname: Stuen
authors.affiliation: Department of Environmental and Health Studies, Telemark University College, Bø, Norway.
authors.forename: Andrew
authors.initials: A
authors.lastname: Jenkins
authors.affiliation: Department of Laboratory Services, Division of Medical Services, County Hospital Ryhov, Jönköping, Sweden.
authors.forename: Olaf
authors.initials: O
authors.lastname: Dienus
authors.affiliation: Host-Microbe Interactions, Institute of Medical Biology, UiT The Arctic University of Norway, Tromsø, Norway.
authors.forename: Renate S
authors.initials: RS
authors.lastname: Olsen
authors.affiliation: Institute of Medical Biology, UiT The Arctic University of Norway, Tromsø, Norway.
authors.forename: Bjørn-Erik
authors.initials: BE
authors.lastname: Kristiansen
authors.affiliation: Institute of Microbiology, Armed Forces Medical Services, Oslo, Norway.
authors.forename: Reidar
authors.initials: R
authors.lastname: Mehl
authors.affiliation: Department of Laboratory Services, Division of Medical Services, County Hospital Ryhov, Jönköping, Sweden.
authors.forename: Andreas
authors.initials: A
authors.lastname: Matussek
mesh_terms: D000818:Animals; D001110:Arctic Regions; D001898:Borrelia / Q000235:genetics / Q000302:isolation & purification*; D002371:Cat Diseases / Q000453:epidemiology / Q000382:microbiology*; D002415:Cats; D004283:Dog Diseases / Q000453:epidemiology / Q000382:microbiology*; D004285:Dogs; D005260:Female; D018884:Ixodes / Q000502:physiology*; D008297:Male; D009664:Norway; D015995:Prevalence; D013984:Tick Infestations / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*
keywords: Borrelia burgdorferi; Cat; Distribution limit; Dog; Ixodes ricinus; Northwestern Europe