Group A rotaviruses of the family Reoviridae is one of the important intestinal pathogens causing diarrhea in piglets and humans. A human-porcine reassortment rotavirus, GDJM1, was identified from outbreak of diarrhea in suckling piglets and it associated with 60.00% (324/540) morbidity and 20.99% (68/324) mortality in Guangdong Province of China in 2022. Thus, to further characterize the evolutionary diversity of GDJM1, all gene segments were analyzed. The genome constellation was G9-P[19]-I5-R1-C1-M1-A8-N1-T1-E1-H1. Nucleotide sequence identity and phylogenetic analyses showed that the VP6, VP7, NSP4 and NSP5 genes of GDJM1 were the most closely related to the respective genes of porcine strains, with the highest homology ranging from 95.65–98.55% identity. The remaining seven genes (VP1-VP4, NSP1-NSP3) were the most closely related to human strains, with the highest homology ranging from 91.83–96.69% similarity. Therefore, it is likely that GDJM1 emerged as the result of genetic reassortment between porcine and human rotaviruses. To our knowledge, this is the first report that a human-porcine reassortment G9P[19] RVA strain has been identified in mainland China, which providing important insights into evolutionary characterization of G9P[19] RVA strain, and reveals that the strain has a potential risk of cross-species transmission.

Porcine parvoviruses (PPVs) are a group of small non-enveloped viruses with seven species (porcine parvovirus 1–7, PPV1-7) have been identified. In this study, a novel porcine parvovirus, provisionally named porcine parvovirus 8 (PPV8), was initially identified via high-throughput sequencing (HTS) in porcine reproductive and respiratory syndrome virus-positive samples collected from swine herds in Guangdong province, 2021. The nearly full-length genome of PPV8 strain GDJM2021 is 4,380 nucleotides in length with two overlapping open ORFs encoding NS1 and VP1 respectively. Sequence analysis indicated that PPV8 shared 16.23–44.18% sequence identity at the genomic levels to PPV1-7 with the relatively highest homology to PPV1. PPV8-GDJM2021 shared 31.86–32.68% aa sequence identity of NS1 protein with those of PPV1 and porcine bufavirus (PBuV), and formed an independent branch neighboring to those formed by members of the genus Protoparvovirus. Of the 211 clinical samples collected from 1990 to 2021, 37 samples (17.5%) distributed over 12 regions in China were positive for PPV8 with time spanning 24 years (1998–2021). To our knowledge, this is the first report on the genomic characterization of the novel PPV8 and its epidemiological situations in China.