Bat-associated ticks as a potential link for vector-borne pathogen transmission between bats and other animals

Potentially zoonotic pathogens have been previously detected in bat-associated ticks, but their role in disease transmission and their frequency of feeding on non-bat hosts is poorly known.

We used molecular blood meal analysis to reveal feeding patterns of the bat-associated tick species Ixodes ariadnae, I. simplex, and I. vespertilionis collected from cave and mine walls in Central and Southeastern Europe. Vertebrate DNA, predominantly from bats, was detected in 43.5% of the samples (70 of 161 ticks) but in these ticks we also detected the DNA of non-chiropteran hosts, such as dog, Canis lupus familiaris, wild boar, Sus scrofa, and horse, Equus caballus, suggesting that bat-associated ticks may exhibit a much broader host range than previously thought, including domestic and wild mammals. Furthermore, we detected the zoonotic bacteria Neoehrlichia mikurensis in bat ticks for the first time, and other bacteria, such as Bartonella and Wolbachia.

In the light of these findings, the role of bat ticks as disease vectors should be urgently re-evaluated in more diverse host systems, as they may contribute to pathogen transmission between bats and non-chiropteran hosts.