Borrelia miyamotoi is widespread in Ixodes ricinus ticks in southern Norway

From April to October 2007, host-seeking Ixodes ricinus ticks were collected from four locations in southern Norway; Farsund, Mandal, Søgne and Tromøy, respectively. Larvae (n=210), nymphs (n=1130) and adults (n=449) were investigated for infection with Borrelia miyamotoi by real-time polymerase chain reaction (PCR) amplification of part of the 16S rRNA gene. Results were verified by direct sequencing of the PCR amplicon generated from the rrs (16S)-rrl (23S) intergenetic spacer. B. miyamotoi was detected at all sites and throughout the period of questing activity, with infection prevalence (≤1.26%) similar to what has been seen in other European countries. Detection of the relapsing fever spirochete at all locations indicates a wide distribution in southern Norway. This is the first report of B. miyamotoi prevalence in ticks collected from Norway. As not much is known about the spatiotemporal dynamics of this relatively recently discovered pathogen, the conclusions of this study significantly add to the knowledge regarding B. miyamotoi in this region.