First molecular detection of porcine parvovirus 5 in slaughtered pigs from Southern Vietnam.

Porcine parvovirus 5 (PPV5) has been increasingly reported in swine populations in several countries, but no molecular evidence of this virus has been documented in Vietnam. This study investigated the molecular positivity rate of PPV5 in slaughtered pigs from southern Vietnam, assessed its co-detection patterns with porcine circoviruses (PCV2, PCV3, and PCV4), and preliminarily characterized Vietnamese PPV5 strains based on partial VP1 gene sequences. Eighty lung samples collected from four localities in southern Vietnam during 2024-2025 were examined by PCR. PPV5 DNA was detected in 44/80 samples (55.0%), providing the first molecular evidence of PPV5 detection in Vietnamese pigs. PPV5 was co-detected with PCV2 in 28.8% of samples and with PCV3 in 5.0% of samples, whereas PCV4 was not detected. Representative PPV5-positive samples were selected for partial VP1 gene sequencing (GenBank accession numbers PX233317-PX233319). Phylogenetic analysis showed that the Vietnamese PPV5 strains clustered within the global PPV5 lineage and shared ≥ 99.0% nucleotide identity with previously reported PPV5 reference strains from the United States, Poland, South Korea, China, Colombia, and Russia. One strain (HCMC22) carried two distinct amino acid substitutions (T150A and T163P) within the analyzed VP1 fragment. These findings provide the first molecular evidence of PPV5 detection in Vietnamese pigs, contribute additional sequence data from Vietnam, and support the need for broader surveillance and genome-scale studies to better understand the epidemiology and genetic diversity of PPV5 in swine populations.