Screening of Domestic Cats from North-Eastern Hungary for Hepatozoon felis and Cytauxzoon europaeus That Cause Infections in Local Wildcat Populations

Among vector-borne protozoa Hepatozoon felis and Cytauxzoon europaeus are considered emerging species in felids in Europe. To investigate the presence of these two protozoa 127 domestic cats and 4 wildcats were screened by PCRs targeting the 18S rRNA gene of Hepatozoon spp. and piroplasms, as well as the cytb gene of Cytauxzoon spp. The samples were collected inside and outside a region of Hungary, where both protozoan groups are endemic in wildcats. Among domestic cats, one proved to be infected with H. felis. Furthermore, spleen samples of four wildcats were also examined, among which three tested positive for H. felis, and one had co-infection with C. europaeus. Importantly, H. felis from the co-infected wildcat belonged to genogroup II, similarly to H. felis from the positive domestic cat. Based on phylogenetic evidence, this genogroup probably represents a separate species from genogroup I of H. felis, which was hitherto reported from Mediterranean countries in Europe. The two other wildcats also harbored H. felis from genogroup I. Neither Hepatozoon nor Cytauxzoon infections were detected outside the recently discovered endemic region. In conclusion, this study demonstrates for the first time in Europe that H. felis from genogroup II may emerge in free-roaming domestic cats in regions where this protozoan parasite is endemic in wildcats.