Tick-borne pathogens infecting urban domestic dogs from a highland swamp area from Paraíba, northeastern Brazil.

Tick-borne diseases represent important illnesses in dogs, but information about their occurrence in some regions of northeastern Brazil is still limited. Considering the possible differences in the distribution of these agents among the various regions of the country, this study aimed to investigate the prevalence of Babesia vogeli, Ehrlichia canis, Hepatozoon spp., and Borrelia spp., as well as factors associated with these infections in urban dogs from the Brejo Paraibano microregion. To this end, canine blood samples were analyzed using TaqMan real-time PCR protocols or conventional PCR. Overall, of the 398 dogs sampled 109 (27.3%) tested positive for at least one of the four pathogens investigated. Deeming each pathogen, B. vogeli was detected in 25 animals, E. canis in 32, and Hepatozoon spp. in 71, the latter confirmed as H. canis by DNA sequencing in at least 10 dogs. Borrelia spp. was not detected in any dog. After multivariate analysis, for B. vogeli, the presence of apathy (P = 0.034), anemia (P = 0.035), and high tick infestation (P = 0.017) were associated. No variable was associated with positivity for E. canis (P > 0.05). For Hepatozoon (including H. canis), the ingestion of untreated water (P = 0.002) was associated. The results confirm the circulation of pathogens of veterinary importance in the state, and report, for the first time, the molecular detection of Hepatozoon canis in the state. Furthermore, they provide information on associated factors that contribute to the planning of surveillance and control measures in the region.