Genetic characterization and emergence of a novel subgenotype of duck circovirus in South Korea, 2022-2023.

Abstract

In this study, we examined samples from 135 deceased ducks, collected from 27 farms across South Korea between 2022 and 2023, and determined that the positivity rate for duck circovirus (DuCV) was 66.7%. Whole-genome sequencing was performed on 18 DuCV strains from the DuCV-positive farms. Phylogenetic analysis revealed that 13 of the 18 strains belonged to genotype Ib, while the remaining five strains belonged to genotype Id, marking the first identification of this genotype in Korea. Further phylogenetic and recombination analysis showed that the DuCV-Ib strains could be categorized into two distinct sublineages. Notably, two genotype Ib strains appear to have originated through intra-sublineage recombination. In light of the high prevalence, genetic diversity, and ongoing evolution of DuCVs in domestic duck populations in Korea, these findings underscore the importance of ongoing surveillance, as well as enhanced disease prevention and control measures.