Serologic and Molecular Diagnostic Survey of Babesia spp. Infections in Hunting Dogs from Southern Italy

Canine babesiosis is a potentially serious canine vector-borne disease (CVBD) caused by intraerythrocytic protozoan parasites of the genus Babesia. Clinical signs of babesiosis include moderate to severe hemolytic anemia, fever, anorexia, depression, pallor, and splenomegaly. Infections are tick-transmitted, and geographic distribution throughout Europe is expanding along with the spread of the tick species Dermacentor reticulatus and Rhipicephalus sanguineus. The present study aimed to perform a serological and molecular diagnostic survey of Babesia spp. infections in hunting dogs from southern Italy. Blood samples were collected from hunting dogs (n=1,311) without any specific signs associated with babesiosis in the Avellino, Napoli, and Salerno provinces of Campania region of southern Italy. Signalment and history of tick infestation were recorded for each dog at the time of blood collection. Serology testing was performed by two enzyme-linked immunosorbant assays (ELISAs), with one designed to detect canine antibodies to B. canis and B. vogeli and the other designed to detect canine antibodies to B. gibsoni. All samples were tested by real-time polymerase chain reaction (RT-PCR) assays for the presence of two large-form Babesia, Babesia canis and Babesia vogeli, and one small-form Babesia, Babesia gibsoni. Nearly half (634/1311, 48.4%) of all hunting dogs had a history of tick infestation. Seropositive rates were 14.0% (184/1311) for B. canis/B. vogeli and 0.2% (3/1311) for B. gibsoni. PCR-positive rates for B. canis and B. vogeli were 0.2% (2/1311) and 1.1% (15/1311), respectively. No dog tested positive by RT-PCR for B. gibsoni. Salerno had the highest prevalence of Babesia spp. infections with 22.5% of dogs testing positive by either PCR or ELISA followed by Avellino (15.7%) and Napoli (8.6%). The present study represents the first large-scale survey of Babesia spp. infections in hunting dogs from southern Europe and demonstrates that hunting dog populations in southern Italy are at risk for babesiosis. Further studies are needed to determine the prevalence of clinical babesiosis in this at-risk population and to evaluate the relationship between hunting dogs and sympatric populations of wild animals in the epidemiology of Babesia spp.