The first report of porcine parvovirus 8 detection and genetic analysis in South Korea

Porcine parvoviruses (PPVs) are small, non-enveloped, single-stranded DNA viruses that infect pigs. Recently, a novel porcine parvovirus 8 (PPV8) was identified in China and subsequently detected in several countries, suggesting its global distribution. This study aimed to investigate the presence and molecular characteristics of PPV8 in Korea using diagnostic submission samples originally collected for screening of major porcine viral diseases. From October to December 2023, a total of 723 pooled samples, derived from 3,175 individual serum, nasal swab, and oral fluid samples from 40 pig farms, were screened for PPV8 by PCR. PPV8 was detected in 87.5% (35/40) of farms and 24.6% (178/723) of pooled samples, with oral fluid pools showing the highest apparent positivity. Among the 294 serum pools analyzed, PPV8 alone was detected in 10 samples (3.4%). In contrast, 45 samples showed co-detection of PPV8 with other viruses. Within these co-detected samples ( n = 45), PRRSV 2 was the most frequent (33.3%, 15/45), followed by PRRSV 1 (22.2%, 10/45) and PCV2 (8.9%, 4/45). Samples positive for all three viruses were also identified (6.7%, 3/45). Whole-genome sequencing of representative samples revealed two genetically distinct clades circulating in Korea, which exhibited amino acid differences in predicted antigenic epitopes of the VP1/VP2 region. These findings suggest that PPV8 is already widespread in Korean pig farms and should be considered as part of routine diagnostic surveillance in herds experiencing endemic viral infections.