Bartonellaspp. detection in ticks,Culicoidesbiting midges and wild cervids from Norway

Bartonellaspp. are fastidious, gram-negative, aerobic, facultative intracellular bacteria that infect humans, and domestic and wild animals. In Norway,Bartonellaspp. have been detected in cervids, mainly within the distribution area of the arthropod vector deer ked (Lipoptena cervi). We used PCR to survey the prevalence ofBartonellaspp. in blood samples from 141 cervids living outside the deer ked distribution area (moose [Alces alces,n = 65], red deer [Cervus elaphus,n = 41] and reindeer [Rangifer tarandus,n = 35]), in 44 pool samples of sheep tick (Ixodes ricinus, 27 pools collected from 74 red deer and 17 from 45 moose) and in biting midges of the genusCulicoides(Diptera: Ceratopogonidae, 120 pools of 6,710 specimens).BartonellaDNA was amplified in moose (75.4%, 49/65) and in red deer (4.9%, 2/41) blood samples. All reindeer were negative. There were significant differences inBartonellaprevalence among the cervid species. Additionally,Bartonellawas amplified in two of 17 tick pools collected from moose and in 3 of 120 biting midge pool samples. TheBartonellasequences amplified in moose, red deer and ticks were highly similar toB. bovis, previously identified in cervids. The sequence obtained from biting midges was only 81.7% similar to the closestBartonellaspp. We demonstrate thatBartonellais present in moose across Norway and present the first data on northern Norway specimens. The high prevalence ofBartonellainfection suggests that moose could be the reservoir for this bacterium. This is the first report of bacteria from theBartonellagenus in ticks from Fennoscandia and in Culicoides biting midges worldwide.

Automated summary

The study revealed varying prevalence of Bartonella in moose and red deer in Norway, with Bartonella also detected in ticks and biting midges. Moose may serve as a reservoir for Bartonella. This study marks the first report of Bartonella genus in ticks from Fennoscandia and Culicoides worldwide.