Tick reservoirs for piroplasms in central and northern Italy

Ticks, collected in central and northern Italy from pets, livestock, wild animals and the environment (n=2107), were identified by microscopy and processed by molecular diagnostics to determine the species that act as a reservoir for piroplasms. A total of 11 ixodid tick species were identified, with five of them proving to be piroplasm positive. Molecular diagnostics identified Theileria equi and eight Babesia species in 52 adult specimens, mostly (n=50) removed from piroplasm-free vertebrate hosts. Ixodes ricinus hosted the highest number of species, although the highest infection rate was recorded in Hyalomma marginatum (9.1%), followed by I. ricinus (5.1%), Dermacentor marginatus (5%), Rhipicephalus turanicus (3.1%) and R. sanguineus (1.2%). Novel tick/pathogen associations were detected, suggesting that certain tick species (such as Hy. marginatum, R. sanguineus and I. ricinus) are vector of more piroplasm species than previously thought. Trans-stadial maintenance of the piroplasms was observed in each positive tick species; vertical transmission of B. canis canis was demonstrated in R. sanguineus. Finally, the detection of Babesia sp., B. microti-like species and B. rodhaini, phylogenetically related to zoonotic species, suggests that the human population could be at risk of infection in the studied area.