Isolation, characterization and whole-genome analysis of G9 group a rotaviruses in China: Evidence for possible Porcine–Human interspecies transmission

Group A rotaviruses (RVAs) are major causes of severe gastroenteritis in infants and young animals. To enhance our understanding of the relationship between human and animals RVAs, complete genome data are necessary. We screened 92 intestinal and stool samples from diarrheic piglets by RT‒PCR targeting the VP6 gene, revealing a prevalence of 10.9%. RVA was confirmed in two out of 5 calf samples. We successfully isolated two porcine samples using MA104 cell line. The full-length genetic constellation of the two isolates were determined to be G9-P[23]-I5-R1-C1-M1-A8-N1-T7-E1-H1, with close similarity to human Wa-like and porcine strains. Sequence analysis revealed the majority of genes were closely related to porcine and human RVAs. Phylogenetic analysis revealed that these isolates might have their ancestral origin from pigs, although some of their gene segments were related to human strains. This study reveals evidence of reassortment and possible interspecies transmission between pigs and humans in China.