Résumé
Objective@#To analyze the genotype diversity and phylogenetic characterization of norovirus(NoV) in patients with diarrhea from Anhui province.@*Methods@#NoV positive fecal specimens from sentinel hospitals were collected from January, 2016 to December, 2017. The samples were detected by Real-time fluorescent quantitative PCR. Positive samples were of randomly selected and amplified by RT-PCR and the products were sequenced. Phylogenetic tree was constructed by the Neighbor-Joining method based on partial VP1 gene regions of NoV to perform phylogenetic analysis.@*Results@#A total of 263 NoV positive samples were genotyped, of which 239 belonged to genogroup II, 24 belonged to genogroup I. Fifty-five positive samples were successfully sequenced. There were 6 NoV GII genotypes, which included GII.2, 3, 4/Sydney_2012, 13, 17 and 21, while NV GII.17 and GII.4 were the dominant genotypes from 2016 to 2017. The predominant genotype was GII.4/Sydney 2012 (47.27%, 26/55), followed by GII.17 (23.64%, 13/55) and GII.2 (14.55%, 8/55). Phylogenetic tree showed that 26 strains belonged to genotype GII.4/Sydney 2012, NoV. The nucleotide homology among the 26 VP1 genes was 97.8% to 100%. Analysis of the partial VP1 genes of 26 strains showed that it shared the highest homology of 98.9% with the strain of GII.4Sydney2012 (GenBank ID: KU720515). However, the prevailing genotype in the Anhui province has shifted on two separate occasions, the GII.17 strain was dominant in 2016, and the GII.4/Sydney 2012 strain was dominant in 2017.@*Conclusions@#NoV GII was the major pathogen causing sporadic diarrhea in Anhui province during from 2016 to 2017, the genotypes are widely distributed, and shifted into the two predominant strains.