Canine exposure to vector-borne pathogens in a rural Brazilian landscape

Vector-borne pathogens (VBPs) of medical and veterinary concern have mostly been studied in urban dog populations, while animals in rural settings, with limited access to ectoparasite prevention, have received less attention. In this study, we assessed canine exposure to VBPs in a rural Brazilian landscape. From August to October 2024, we collected 155 blood samples from dogs domiciled in a rural area of the municipality of Garanhuns, Pernambuco, Northeastern Brazil. Samples were assessed using an immunofluorescence antibody test (IFAT) to detect antibodies against Trypanosoma cruzi and using a rapid immunochromatographic test combined with an ELISA to detect Leishmania infantum antibodies. In addition, each sample was tested using a qualitative ELISA to detect D. immitis antigens and antibodies against Anaplasma phagocytophilum/Anaplasma platys, Ehrlichia canis/Ehrlichia ewingii, and Borrelia burgdorferi sensu lato. A total of 56.1% (87/155) of samples were reactive to at least one pathogen. Specifically, in 5.1% (8/155) were detected anti-T. cruzi antibodies, and in four of these samples (2.5%, 4/155) were co-detected antibodies anti-L. infantum. Antibodies against Ehrlichia spp. were observed in 50.9% (79/155), Anaplasma spp. in 8.3% (13/155), and B. burgdorferi in 0.6% (1/155). Antigens for D. immitis were detected in 1.2% (2/155). No statistical associations were observed on variables (sex, mobility, overnight stay and presence of ectoparasites) and pathogen seropositivity. In conclusion, dogs from rural areas are exposed to VBPs, which requires the use of ectoparasiticide preventive compounds to avoid ectoparasite infestation and reduce the risk of pathogen exposure.