Molecular detection and genetic characterization of Borrelia spp. and piroplasmids in wildlife blood and host-attached ticks from Jeonnam Province, South Korea.

Studies simultaneously examining tick-associated pathogens in wildlife blood and host-attached ticks remain limited in South Korea. We investigated selected Borrelia spp. and piroplasmids in blood samples from 34 animals-16 Korean water deer (Hydropotesinermis), seven raccoon dogs (Nyctereutes procyonoides), and 11 wild boars (Sus scrofa)-and in 246 host-attached ticks collected from 13 animals of the same species-three Korean water deer, six raccoon dogs, and four wild boars-in Jeonnam Province. Paired blood and tick samples were available from eight animals. The ticks were processed as 186 molecular test units and identified as Haemaphysalis longicornis, Amblyomma testudinarium, and Ixodes nipponensis. Borrelia garinii DNA was detected in 156 of 186 test units (83.9%), corresponding to a minimum infection rate (MIR) of 63.4% (156/246 ticks). Twenty representative flaB-positive amplicons yielded identical sequences within the analyzed 347-bp fragment. Second-locus analysis of the 5S-23S rRNA intergenic spacer region in one representative test unit per tick species supported B. garinii identification in those three samples. A Babesia lineage closely related to B. gibsoni was detected in 22 of 34 blood samples (64.7%) and six of 186 tick test units (3.2%; MIR, 2.4%). Borrelia theileri was detected in all three wildlife species, with PCR positivity of 54.5% in wild boars, 37.5% in Korean water deer, and 28.6% in raccoon dogs. Theileria luwenshuni and T. capreoli were detected only in Korean water deer, at 50.0% and 31.3%, respectively. Among the eight paired animals, no concordant pathogen taxon was detected in blood and attached-tick test units. These findings provide regional molecular data on Borrelia spp. and piroplasmids at the wildlife-tick interface. However, the small convenience sample, partial grouping of H. longicornis, use of host-attached ticks, and limited second-locus confirmation preclude inference regarding reservoir competence, transmission cycles, or vector involvement.