Seroprevalence and Current Infections of Canine Vector-Borne Diseases in Costa Rica.

Domestic dogs may carry several vector-borne pathogens, including zoonotic agents, especially in tropical regions like Central America. The epidemiology of these pathogens is prone to change due to urbanization, trade and travel as well as climate change, necessitating repeated monitoring. This study aims to present a comprehensive picture of canine vector-borne diseases in Costa Rica, combining data on seroprevalence with molecular species identification of the causative pathogens. In this survey, 294 dogs from all seven provinces of Costa Rica were included. After a clinical examination, diagnostic blood samples were analyzed with regard to packed cell volume (PCV) and presence of microfilaria. Serum samples were tested for antibodies against spp., spp., spp., sensu lato (s.l.) as well as antigen of . Seropositive and microfilaremic blood samples were analyzed by PCR to detect current infections and identify the pathogen species. Overall, 45.24% (133/294, 95% CI: 39.45-51.11%) of dogs were seropositive for at least one of the tested pathogens. Seroprevalence was highest for spp. (39.46%, 116/294, 95% CI: 33.83-45.29%), followed by spp. (23.13%, 68/294, 95% CI: 18.43-28.38%), spp. (13.27%, 39/294, 95% CI: 9.61-17.69%), and s.l. (0.34%, 1/294, 95% CI: 0.01-1.88%). Generalized linear mixed models indicated a significant association of -, - and -seropositivity, as well as a significant effect of age and breed on -seropositivity. Furthermore, a statistically significant negative effect of -, -, and -seropositivity on PCV was found. Regarding current infections, DNA was detected in 51.72% (60/116, 95% CI: 42.26-61.10%) of -seropositive dogs, while and were not detected. Furthermore, 10.26% (4/39, 95% CI: 2.87-24.22%) of -seropositive dogs were coinfected with and , while one animal (2.56%, 95% CI: 0.65-13.48%) was infected with only. Among -seropositive dogs, and were detected in one animal each (1.47%, 1/68, 95% CI: 0.04-7.92%). antigen was detected in 4.42% (13/294, 95% CI: 2.38-7.44%) of dogs. In microfilaremic animals, as well as infections were identified. This survey demonstrates that canine vector-borne pathogens, including zoonotic agents like and , are widespread in Costa Rica. Thus, protection of dogs from disease-transmitting vectors is recommended from an animal welfare as well as public health perspective.