摘要：
Objective To analyze epidemiological and etiological characteristics of norovirus in Longhua District, Shenzhen. Methods Three hundred and seventeen suspected cases among the 29 clusters of epidemic gastroenteritis from 6 subdistricts (Guanhu, Minzhi, Longhua, Dalang, Fucheng and Guanlan) in Longhua District, Shenzhen from October 2016 to September 2017 were selected as research subjects. A total of 317 anal swab specimens of the subjects were collected. Fluorescence quantitative PCR was adopted for norovirus examination of the samples and reverse transcription PCR for further examination of positive specimens. Meanwhile, gene amplification was conducted in polymerase and capsid area, and sequencing and phylogenetic analysis were conducted to determine virus genotypes.Results For the 317 suspected cases, 156 were laboratory confirmed, among which 99 were children under five years old (63.46%, 99/156). The 29 reported clusters of epidemic gastroenteritis were mainly from kindergartens, accounting for 75.9% (22/29). Among the 317 specimens, 156 were positive of norovirus GII nucleic acid, with a positive rate of 49.21%. Norovirus GI was undetected. Reverse transcription PCR amplification was performed for the virus polymerase and capsid area in the 156 positive specimens. Eighty two samples were positive and 82 sequences were obtained. Phylogenetic tree construction results indicated that there were four genotypes causing norovirus epidemics in Longhua District, Shenzhen from October 2016 to September 2017, including GⅡ.P16-GⅡ.2, GⅡ.Pe-GⅡ. 4 Sydney 2012, GⅡ.P17-GⅡ.17 and GⅡ.P12-GⅡ.3 genotypes. GII. P16-GⅡ.2 norovirus caused 18 clusters, accounting for 62.1% (18/29). Conclusions Surveillance of norovirus epidemics in Longhua District, Shenzhen should be furtherly enhanced and children under 5 years old should be paid close attention. Meanwhile, the emergence of mutants need to be closely monitored.%目的 分析深圳市龙华区诺如病毒疫情流行特征及病原学特点.方法 选取2016年10月—2017年9月期间深圳市龙华区共6个街道(观湖、民治、龙华、大浪、福城和观澜)29起聚集性胃肠炎疫情中的317例疑似病例作为研究对象.收集研究对象肛拭子标本,共计317份,采用荧光定量PCR方法对样品进行诺如病毒检测,阳性样本进一步用逆转录PCR法同时对聚合酶区-衣壳区进行基因扩增,并进行测序和进化分析以鉴定其基因型.结果 317例疑似病例中,实验室确诊156例,其中5岁以下儿童99例(63.46%,99/156).29起聚集性胃肠炎疫情报告单位主要为幼儿园,占75.9%(22/29).在317份标本中,156份为诺如病毒GⅡ核酸阳性,阳性率为49.21%.未检出诺如病毒GI.对156份诺如病毒GⅡ核酸阳性的标本进行聚合酶区-衣壳区序列逆转录PCR扩增,共82份阳性,获得82株毒株序列.系统发生树构建结果发现,2016年10月—2017年9月期间,引起深圳市龙华区诺如病毒疫情的基因型有4种,包括GⅡ.P16-GⅡ.2、GⅡ.Pe-GⅡ.4 Sydney 2012、GⅡ.P17-GⅡ.17和GⅡ.P12-GⅡ.3.其中,GⅡ.P16-GⅡ.2引起的有18起,占62.1%(18/29). 结论 深圳市龙华区应进一步加强诺如病毒聚集性疫情监测,重点关注幼儿园5岁及以下儿童,并且要重点监测是否有变异株出现.
