Assessing Zoonotic Risk in a Fenced Natural Park in Northwestern Italy: Integrating Camera Traps for a Vector-Host Approach to Tick-Borne Pathogens

Rachele Vada ^* Stefania Zanet Flavia Occhibove Anna Trisciuoglio Amir Reza Varzandi Ezio Ferroglio

• Department of Veterinary Sciences, School of Agriculture and Veterinary Medicine, University of Turin, Turin, Piedmont, Italy

Tick-borne diseases are among the most widespread emerging zoonotic diseases, and their circulation in the environment is influenced by a broad range of abiotic and biotic factors, including the abundance of vectors and vertebrate hosts. In this study, we estimated the prevalence of tick-borne pathogens and the impact of wildlife head count on their circulation in a lowland natural area in North-Western Italy. We used ticks and camera trap pictures collected from 14 sampling points every two weeks for one year, and detected pathogens through molecular analyses: Babesia capreoli, B. microti-like, Borrelia burgdorferi sensu lato, Rickettsia of the spotted fever group (SFG), Theileria capreoli and Anaplasma phagocytophilum. We modelled the presence of B. capreoli, B. microti-like, B. burgdorferi s.l. and SFG Rickettsia on head counts of wild ungulates and mesocarnivores, testing a global model including all collected ticks and an I. ricinus nymphs-only model, being this (species and developmental stage) the greatest source of zoonotic infection risk. The highest prevalences were obtained for B. microti-like (13%) and SFG Rickettsia (11%) and, for most pathogens, no differences were detected among tick species and developmental stages. Mesocarnivores showed an additive effect on B. microti-like and B. burgdorferi s.l., while wild ungulates, non-competent for transmission of our target pathogens, showed a dilutive effect. These findings confirm the circulation of relevant tick-borne pathogens in the study area and show the use of camera trap data in predicting tick-borne pathogens’ risk by targeting host species, which may have an indirect impact and are more easily addressed by monitoring and control strategies.