Title : Isolation and full genomic characterization of G9 group: A rotavirus in China
Abstract:
Young animals and infants are vulnerable to severe gastroenteritis caused by Group A rotaviruses (RVAs). However, A lack of genomic data exists on the rotavirus A strains circulating in farm animals in China that may infect humans. We therefore screened the fecal samples collected from diarrheic pigs and calves from different farms in China for RVA using RT-PCR, followed by culture of positive RVA samples in the MA-104 cell line. Ten porcine samples (10 %) tested positive out of 100 samples. Likewise, RVA was confirmed in the two samples out of 5 samples from calves. We successfully isolated two porcine samples with cytopathic effects (CPE) showing detachment, granulation, and clustering of the inoculated cells after 5 blind passages. A metagenomic analysis of these isolates was conducted. This study reports on the first complete genome analysis of Chinese G9P[23] porcine RVA strain, resulting in the following genotype constellation: G9-P[23]-I5-R1-C1-M1-A8-N1-T7-E1-H1, a known porcine genotype constellation. There are segments of the genome resemble those isolated from human samples in suspected cases of zoonotic infection, despite the fact that the rotavirus A genotype identified here has a pig-like genome constellation. However, in this study, it was observed that both RVA-positive samples obtained from calves belonged to the G8P[1] genotype. As a result, such viruses may serve as a source of variable gene segments for re-assortment with other viruses, resulting in vaccination breakdown. It is suggested that more human and pig strains be characterized in China to aid in the rational deployment of vaccinations or other RVA prevention and control approaches. Additionally, the development of a vaccine specifically targeting porcine G9 rotaviruses is necessary to effectively prevent infections in China.
