广东省2021年诺如病毒感染疫情流行病学特征分析

Prevalence and genetic characteristics of norovirus epidemics in Guangdong province,2021

目的分析2021年广东省诺如病毒聚集性或暴发疫情的流行病学特征。方法收集广东省2021年1—12月诺如病毒感染疫情样本及相关基本信息,通过实时荧光定量PCR(qRT-PCR)对样本进行诺如病毒的鉴定,筛选诺如病毒GⅠ型和GⅡ型阳性样本,通过PCR扩增、建库、测序、序列拼接后对其进行基因分型。结果2021年广东省共报告141起诺如病毒感染疫情,其中92.91%(131起)的疫情发生在托幼机构或学校;疫情的流行季节为冬春季。73起疫情(51.77%)确定了基因分型。94.52%(133起)的诺如病毒感染疫情由GⅡ型引起,其中GⅡ.2[P16]和GⅡ.4[P31]分别占比39.13%和23.19%。结论广东省2021年诺如病毒疫情主要发生在托幼机构和学校,GⅡ.2[P16]和GⅡ.4[P31]分别是春季和冬季的主要流行型别,仍需继续加强诺如病毒疫情监测以及分子分型研究。

Objective To analyze prevalence and genetic characteristics of clusterings/outbreaks of norovirus(NV)infection in Guangdong province in 2021.Methods We collected the information on all laboratory confirmed NV infection clusterings(3 correlated cases in 3 days at a venue)and outbreaks(20 correlated cases in 7 days at a venue)reported in Guangdong province throughout 2021.Anal swab/stool specimens of the reported cases were sampled for NV detection with quantitative real-time PCR(qRT-PCR).The NV GⅠand GⅡstrains screened out from positive specimens were genotyped with PCR amplification,library preparation,gene sequencing and splicing.Results Of a total of 141 NV clusterings/outbreaks reported in the province during the year,92.91%occurred in nurseries or schools and mainly during winter and spring seasons.For the genotyped NV strains isolated from specimens of 73 outbreaks(51.77%of all epidemics),94.52%were NV GⅡ,with GⅡ.2[P16]and GⅡ.4[P31]accounting for 39.13%and 23.19%of all NV strains,respectively.Conclusion In Guangdong province during 2021,the norovirus clusterings/outbreaks occurred mainly in nurseries and schools in winter/spring seasons and the majority of the outbreaks were caused by norovirus GⅡ.2[P16]and GⅡ.4[P31].