Etiologic characteristics of norovirus in outbreaks of acute gastroenteritis in Quanzhou from 2014 to 2017

Objective To understand the etiology, genotype and molecular characteristics of acute viral gastroenteritis in Quanzhou from 2014 to 2017. Methods Specimens from 15 outbreaks of acute viral gastroenteritis in Quanzhou area from 2014 to 2017 were collected and real-time fluorescence quantitative PCR was used to detect norovirus GI and GII, sapovirus, astrovirus and rotavirus, and the result were statistically analyzed. Furthermore, specimens positive for norovirus was further subjected to the amplification and sequencing of polymerase and VP1 genes of norovirus, and sequences were analyzed using DNAstar and MEGA7.0 software. Results In this study, 96 specimens from 15 outbreaks of acute viral gastroenteritis were collected, and norovirus was detected in 30 specimens with a positive rate of 31.25%, among which 23 specimens were genotype GII and 7 specimens genotype GI. Meanwhile, 10 specimens were randomly selected for nucleic acid sequence analysis. The result showed that 9 of them were GII.P16/GII.2 and 1 was GI.6. The phylogenetic analysis showed that the new recombinant norovirus subtype GII.P16/GII.2 was highly homologous to the same subtype detected in outbreaks home and abroad recently. Conclusions The main pathogens caused the outbreak of acute viral gastroenteritis in Quanzhou from 2014 to 2017 were norovirus belonging to subtype GII.P16/GII.2 and subtype GI.6, and subtype GII.P16/GII.2 was the predominant strain which was found for the first time in Quanzhou. Key words: Norovirus; Viral gastroenteritis; Phylogenetic analysis; Genotyping