Serologic and molecular diagnostic survey of vector-borne disease-causing pathogens in hunting dogs from Southern Italy

Canine vector-borne diseases (CVBDs) result from a range of pathogens transmitted to dogs by arthropods. The present study aimed to examine a population of hunting dogs from southern Italy using both serological and molecular diagnostic methods for evidence of infection by known pathogens of CVBDs. Blood samples were collected from hunting dogs (n. 1,191) in the Avellino and Salerno provinces of Campania region of southern Italy. Serological testing for Ehrlichia canis, Anaplasma spp., and Borrelia burgdorferi sensu lato-specific antibodies and Dirofilaria immitis-specific antigen was performed using a commercial in-clinic enzyme-linked immunosorbent assay kit, SNAP® 4Dx® Plus. Molecular diagnostic testing for the blood-borne presence of Ehrlichia canis, Ehrlichia chaffeensis, Anaplasma platys, Anaplasma phagocytophilum, Babesia canis, Babesia vogeli, Babesia gibsoni, Dirofilaria immitis, Dirofilaria repens, Hepatozoon canis, and Leishmania spp. was performed by real time polymerase chain reaction (RT-PCR) assays. Seropositive rates for the four individual pathogens were: E.canis 7.7%; Anaplasma spp. 4.2%; D.immitis,1.4%; and B.burgdorferi s.l. 0.3%. PCR positive rates for eight detected pathogens were: H.canis 16.8%; A.platys 2.4%; E.canis 1.9%; B.vogeli 1.6%; Leishmania spp. 0.4%; B.canis 0.2%; D.repens 0.2%; and D.immitis 0.1%. Co-infections were detected at a rate of 2.3% by serology and 2.7% by RT-PCR with Anaplasma/E.canis and E.canis/H.canis co-infections occurring most frequently by serology and PCR, respectively. The results of present survey indicate that hunting dog populations are at risk of CVBDs in southern Italy. Further studies are needed to evaluate the role of hunting dogs in the epidemiology of vector-borne agents and the relationship to sympatric populations of wild animals.