Low prevalence of zoonotic Babesia in small mammals and Ixodes ricinus in Brittany, France.

In order to evaluate the zoonotic risk due to Babesia spp., especially B. microti, we investigated their presence in 597 individuals of five small mammal species and in 2620 questing nymphs of Ixodes ricinus in rural landscapes of Western France (Brittany). Small mammals (rodents and shrews) are indeed suspected to be reservoir hosts for B. microti, and the tick I. ricinus is the vector of the three main zoonotic species in Europe, i.e. B. divergens, B. venatorum and B. microti. Only one bank vole carried B. microti (genotype "Munich") and only 13 and 2 nymphs of Ixodes ricinus ticks carried B. venatorum and B. capreoli respectively. According to these results, prevalences observed for zoonotic Babesia (0.17% for small mammals and 0.50% for ticks), indicate that exposure of humans to this infectious agent is probably low in western France.

Prevalence of Anaplasma phagocytophilum in small rodents in France.

Anaplasma phagocytophilum is an emerging zoonotic tick-borne pathogen affecting a wide range of mammals. Rodents are suspected to be natural reservoirs for this bacterium, but their role in the epidemiologic cycles affecting domestic animals and wild ungulates has not been demonstrated. This study aimed to improve our knowledge on A. phagocytophilum prevalence in Apodemus sylvaticus, A. flavicollis and Myodes glareolus using data collected in 2010 in one area in eastern France and in 2012-2013 in two others areas in western France. Rodents were captured in each site and infection was tested using qualitative real-time PCR assays on either blood or spleen samples. Prevalence showed high variability among sites. The highest prevalence was observed in the most eastern site (with an average infection rate of 22.8% across all species), whereas no rodent was found to be PCR positive in the south-west site and only 6.6% were positive in the north-west of France. Finally, a significant increase in prevalence was observed in autumn samples compared to spring samples in the north-west, but no change was found in the other two sites.