Seroprevalence of Some Vector-Borne Infections of Dogs in Hungary

The first comprehensive study on the prevalence of canine vector-borne pathogens (Anaplasma phagocytophilum, Borrelia burgdorferi, Ehrlichia canis, and Dirofilaria immitis) was carried in Hungary because, except for babesiosis and dirofilariosis caused by Dirofilaria repens, there were no data on their regional distribution and prevalence. In 2011 and 2012, 1305 blood samples were collected from randomly selected, apparently healthy pet dogs in 167 localities of 19 counties of Hungary. All sera samples from dogs were screened for simultaneous qualitative detection of circulating antibodies to E. canis and B. burgdorferi sensu lato and A. phagocytophilum and D. immitis antigen using SNAP (R) 4Dx (IDEXX Laboratories). Overall, 170 dogs (13.0%; 95% confidence interval [CI] 11-15) were serologically positive to one or more of the tested pathogens. A. phagocytophilum was the most prevalent pathogen detected in 102 dogs by antibody titers (7.9%, 95% CI 6.5-9.5), followed by D. immitis (2.4%, 95% CI 1.0-4.0, n = 64) and B. burgdorferi (0.4%, 95% CI 0.0-1.1, n = 11) out of 1305 tested dogs. The least prevalent infection was with E. canis, with only two positive dogs (0.16%, 95% CI 0.03-0.6). Co-infection was found in eight dogs (0.61%, 95% CI 0.29-1.21), of which seven were seropositive to two pathogens (five with A. phagocytophilum and D. immitis, two with A. phagocytophilum and B. burgdorferi). One dog was serologically positive to three pathogens (A. phagocytophilum, B. burgdorferi, and D. immitis). Purebred and crossbred animals did not show significantly different levels of seropositivity. There was no significant association between the gender and the results of diagnostic testing. Logistic regression analysis showed a higher chance of seropositivity in the older dogs.