Huzhou Center for Disease Control and Prevention, 999 Changxing Road, Huzhou, 313000, Zhejiang, China.
Arch Virol. 2020 May;165(5):1121-1128. doi: 10.1007/s00705-020-04599-2. Epub 2020 Mar 27.
Since 2014, novel non-GII.4 norovirus (NoV) genotypes continue to be reported as the main cause of outbreaks worldwide. In this study, we analyzed the epidemiological and genetic features of NoV outbreaks from July 2014 to June 2018 in Huzhou, China. A total of 450 stool samples collected from 51 AGE outbreaks were tested for NoVs by real-time RT PCR. Partial polymerase and capsid sequences of NoV-positive samples were amplified and sequenced for phylogenetic analysis. NoVs were found to be responsible of 84.3% of AGE outbreaks in Huzhou over the past 5 years. Most NoV outbreaks were reported in the cool months (November-March) and occurred in primary schools and kindergartens. Changes in the diversity of genotypes and the distribution of predominant types were observed in recent years. At least eight genotypes were identified, and 91.9% of the genotyped outbreaks were caused by non-GII.4 strains. The top three circulating genotypes during the study period were GII.2[P16], GII.3[P12], and GII.17[P17]. The predominant NoV genotypes in outbreaks have changed from GII.4 variants to GII.17[P17] in 2014-2015, GII.3[P12] in 2015-2016, and then GII.2[P16] in 2016-2018. Non-GII.4 NoVs play an increasingly important role in outbreaks in Huzhou. Continuous surveillance is needed to monitor the emergence of novel NoV strains and help control NoV outbreaks in the next epidemic season.
自 2014 年以来,新型非 GII.4 诺如病毒(NoV)基因型继续成为全球暴发的主要原因。本研究分析了 2014 年 7 月至 2018 年 6 月中国湖州的 NoV 暴发的流行病学和遗传特征。采用实时 RT-PCR 检测了 51 起食源性疾病暴发中采集的 450 份粪便样本。对 NoV 阳性样本的聚合酶和衣壳序列进行扩增和测序,进行系统发育分析。结果发现,5 年来,NoV 是导致湖州食源性疾病暴发的 84.3%的病原体。大多数 NoV 暴发发生在凉爽的月份(11 月至 3 月),发生在小学和幼儿园。近年来,基因型多样性和主要流行型的分布发生了变化。至少鉴定了 8 种基因型,84.9%的基因分型暴发由非 GII.4 株引起。研究期间循环的三种主要基因型是 GII.2[P16]、GII.3[P12]和 GII.17[P17]。2014-2015 年,优势 NoV 基因型从 GII.4 变异株转变为 GII.17[P17],2015-2016 年转变为 GII.3[P12],然后在 2016-2018 年转变为 GII.2[P16]。非 GII.4 NoV 在湖州暴发中发挥着越来越重要的作用。需要持续监测以监测新型 NoV 株的出现,并有助于控制下一个流行季节的 NoV 暴发。