Ticks are important vectors of various pathogens that result in clinical illnesses in humans and domestic and wild animals. Information regarding tick infestations and pathogens transmitted by ticks is important for the identification and prevention of disease. This study was a large-scale investigation of ticks collected from dogs and their associated environments in the Republic of Korea (ROK). It included detecting six prevalent tick-borne pathogens (Anaplasma spp., A. platys, Borrelia spp., Babesia gibsoni, Ehrlichia canis, and E. chaffeensis). A total of 2293 ticks (1110 pools) were collected. Haemaphysalis longicornis (98.60%) was the most frequently collected tick species, followed by Ixodes nipponensis (0.96%) and H. flava (0.44%). Anaplasma spp. (24/1110 tick pools; 2.16%) and Borrelia spp. (4/1110 tick pools; 0.36%) were detected. The phylogenetic analyses using 16S rRNA genes revealed that the Anaplasma spp. detected in this study were closely associated with A. phagocytophilum reported in humans and rodents in the ROK. Borrelia spp. showed phylogenetic relationships with B. theileri and B. miyamotoi in ticks and humans in Mali and Russia. These results demonstrate the importance of tick-borne disease surveillance and control in dogs in the ROK.
