Red fox (Vulpes vulpes) is the most abundant wild canid species in Austria, and it is a well-known carrier of many pathogens of medical and veterinary concern. The main aim of the present study was to investigate the occurrence and diversity of protozoan, bacterial and filarial parasites transmitted by blood-feeding arthropods in a red fox population in western Austria. Blood (n = 351) and spleen (n = 506) samples from foxes were examined by PCR and sequencing and the following pathogens were identified: Babesia canis, Babesia cf. microti (syn. Theileria annae), Hepatozoon canis, Anaplasma phagocytophilum, Candidatus Neoehrlichia sp. and Bartonella rochalimae. Blood was shown to be more suitable for detection of Babesia cf. microti, whilst the spleen tissue was better for detection of H. canis than blood. Moreover, extremely low genetic variability of H. canis and its relatively low prevalence rate observed in this study may suggest that the parasite has only recently been introduced in the sampled area. Furthermore, the data presented here demonstrates, for the first time, the possible vertical transmission of H. canis from an infected vixen to the offspring, and this could explain the very high prevalence in areas considered free of its main tick vector(s).

Eucoleus boehmi (syn. Capillaria boehmi) is a canine trichuroid nematode affecting the upper respiratory airways (i.e., nasal cavity and paranasal sinuses) of dogs, foxes, and wolves. In the past few years, reports in dogs and wild canids have increased from across Europe, but data on its occurrence and distribution in Austria is scanty. A total of 47 red foxes (Vulpes vulpes) from the two westernmost provinces (Tyrol and Vorarlberg) of Austria were therefore examined for the presence of E. boehmi at necropsy. Eggs and adult nematodes were identified morphologically and molecularly (cox1) as E. boehmi. These nematodes were found in 26 (78.8 %) and 13 (92.9 %) foxes from Tyrol and Vorarlberg, respectively, with an overall prevalence of 83.0 % (39/47). The prevalence rate of infection recorded in this study is among the highest in Europe. These results suggest that foxes may represent an important source of infection for dogs and other canids, but further studies are needed to elucidate the transmission dynamics.