Ecological niche modeling of Babesia sp infection in wildlife experimentally evaluated in questing Ixodes ricinus.

Tick-borne diseases and especially those caused by protozoa of the genus Babesia, are gaining increasing attention as emerging zoonotic pathogens. Zoonotic species like B. venatorum and B. microti have wild animals as main reservoir hosts. We propose a habitat suitability model for Babesia spp. to better understand the entity of Babesia presence, to improve diagnostic awareness and to optimize screening and preventive actions. The probability of Babesia spp. presence was estimated by investigation of potential correlation between this protozoa in wild ruminants and the environmental factors that can favour or limit vector and host availability. We developed two separate models to evaluate the separate roles of cervids and alpine chamois for Babesia spp. epidemiology. A comprehensive model using all presence data from all ungulates species was also developed. The overall area suitable for Babesia spp. in this simulation was found to be 3,723 km(2), which corresponds to 15.51% of the background regional territory. The model developed was empirically validated assessing tick abundance in randomly chosen areas classified by the model as moderately or highly suitable for Babesia spp. Collected Ixodidae ticks analysed for Babesia infection by molecular analysis, to confirm the model predictions, indicated a significantly higher prevalence of this infection in areas identified by the model as highly suitable compared to areas classified as only moderately so (chi(2) = 5.05, p<0.05, Odds Ratio- 2.12, Confidence Interval 95%= 1.1-4.1).