Tick Diversity and Pathogen Transmission in Daejeon, Korea: Implications from Companion Animals and Walking Trails

Simple Summary Tick-borne diseases are increasingly spreading due to global warming. Although the migratory abilities of ticks are limited, the spread of ticks between companion animals and humans has increased with the recent increase in the number of companion animals. For this reason, it is important to know the species of ticks that are parasitizing companion animals and whether they carry disease-causing organisms. Our research team collected ticks from pet trails and pet hospitals in the Daejeon area over a period of three years and confirmed the presence of pathogens through polymerase chain reaction (PCR) analysis. As a result of examining approximately 29,200 ticks, the dominant species was found to be H. longicornis, and the presence of four types of pathogens was confirmed. Through this study, we confirmed the possibility of tick-borne disease transmission between companion animals and humans and the emergence of a new tick (A. testudinarium) due to global warming in the Daejeon area.Abstract With the ongoing global warming-induced climate change, there has been a surge in vector-borne diseases, particularly tick-borne diseases (TBDs). As the population of companion animals grows, there is growing concern from a One Health perspective about the potential for these animals to spread TBDs. In this study, ticks were collected from companion animals and the surrounding environment in Daejeon Metropolitan City, Korea, using flagging and dragging, and CO2 trap methods. These ticks were then subjected to conventional (nested) PCR for severe fever with thrombocytopenia syndrome virus (SFTSV), Anaplasma spp., Ehrlichia spp., and Borrelia spp. We identified a total of 29,176 ticks, consisting of three genera and four species: H. longicornis, H. flava, I. nipponensis, and A. testudinarium. Notably, H. longicornis was the predominant species. The presence of A. testudinarium suggested that the species traditionally found in southern regions are migrating northward, likely as a result of climate change. Our PCR results confirmed the presence of all four pathogens in both companion animals and the surrounding environment, underscoring the potential for the indirect transmission of tick-borne pathogens to humans through companion animals. These findings emphasize the importance of the ongoing surveillance of companion animals in the management and control of TBDs.