昆明地区儿童感染的GII型诺如病毒分子分型研究  

Molecular Epidemic Study on Children Infected with GII Norovirus in Kunming,China

作　　者：王莹 曾洪艳 代雷阳 许彬[2] 沈茹[2] 贺晓丽 邱丽娟 WANG Ying;ZENG Hongyan;DAI Leiyang;XU Bin;SHEN Ru;HE Xiaoli;QIU Lijuan(Haiyuan Medical College,Kunming 650106,China;Kunming Children’s Hospital,Kunming 650228,China;Yunnan Key Laboratory of Children's Major Disease Research,Yunnan Institute of Pediatrics,Kunming Children's Hospital,Kunming 650228,China)

机构地区：[1]昆明医科大学海源学院,云南650106 [2]昆明市儿童医院,云南650228 [3]昆明市儿童医院云南省儿科研究所云南省儿童重大疾病研究重点实验室,云南650228

出　　处：《病毒学报》2021年第4期886-893,共8页Chinese Journal of Virology

基　　金：昆明市卫生科技人才培养项目(项目号:2018-SW(后备)-8);昆明市科技计划项目(项目号:2017-11-01-022);昆明市卫健委医药卫生科技计划项目(项目号:2017-1-S-16603)。

摘　　要：了解昆明地区诺如病毒在儿童中的流行特征和分型特点。统计整理昆明地区哨点医院,2018年6月-2019年10月内的1588例通过荧光定量PCR鉴定为诺如病毒(Norovirus,NV)阳性的病例资料,包括检测时间、年龄及性别,分析流行病学特征。收集到其中荧光定量结果显示病毒相对含量较高的485份儿童腹泻标本,通过逆转录PCR方法成功获得107-ORF1和94-ORF2基因序列信息,进一步进行分子分型。昆明地区2018年11月开始,检出NV的病例逐步增加,至2019年1月,NV检出率开始降低。NV相关性腹泻的易感人群为3岁前幼儿,其中1岁以下患儿占40%,1岁~3岁患儿占56%,其余3岁~16岁患儿仅占4%。分子分型结果显示,流行株根据ORF1分为GIIP16、GIIP12、GII31三种亚型,依据ORF2的结果,属于GII.4、GII.2、GII.3个分支。Tajima中性检验预测RdRp(GII.P16),RdRp(GII.P31),VP1(GII.3),VP1(GII.3)的D值分别为-2.03,-1.51,0.14,-1.13,其中大部分D值小于0。其中VP1(GII.3)的D值为正值,有别于其他大部分预测结果,原因可能是样本量不足,需要在未来扩大样本量开展研究。NV对儿童的感染率在各年龄组间存在差异,在3岁以下儿童感染NV患病率较高。病毒呈季节性流行,主要集中在11月到次年2月。针对儿童患者,昆明地区同时流行3种不同基因型病毒株,优势流行株为GII.P31-GII.4。对突变频率较高的样本进行分析,其基因进化不遵循中性模型,需要进一步对病毒间基因重组进行分析。To investigate the epidemic characteristics and typing characteristics of Noroviruses(NVs)infecting children in Kunming City,China.The data of 1588 cases,identified as NV-positive by fluorescence quantitative polymerase chain reaction(PCR)from June 2018 to October 2019 in a sentinel hospital in Kunming City,China,were collected(detection time,age,sex).A total of 107 open reading frame(ORF)1 and 94 ORF2 partial genes were amplified by reverse transcription-PCR,and then molecular typing was carried out.The number of NV+cases increased gradually from November 2018,then began to decrease by January 2019.The susceptible population of NV-related diarrhea was children aged<3 years.Of this susceptible population,40%was<1 year of age,and 56%was aged 1-3 years.Only 4%of NV+children were aged 3-16 years.Molecular typing revealed that 107 samples were classified into three subtypes(GII.P16,GII.P12 and GII.P31)according to ORF1.With regard to ORF2,NVs belonged to three branches(GII.4,GII.2 and GII.3).The Tajima neutral test showed that the D value of RdRp(GII.P16),RdRp(GII.P31),VP1(GII.3)and VP1(GII.3)was-2.03,-1.51,0.14,-1.13,respectivelyinwhich most of the D values are less than 0.Among them,the D value based on VP1(GII.3)was positive,which was different from most of the other prediction results,and may have been because the sample size was too small.The infection rate of NVs in children varied among different age groups,and the prevalence rate of NVs was much higher in children aged<3 years than that in other age groups.The virus epidemic was dependent on the season,and was concentrated mainly from November to February of the following year.For children,there were three subtypes of virus strains in Kunming City,China,and the dominant strain was GII.P31-GII.4.Gene evolution did not follow the neutral model according to the Tajima neutral test,so further analyses of gene recombination among NVs are needed.

关 键 词：诺如病毒 分子分型 急性胃肠炎 

分 类 号：R373.2[医药卫生—病原生物学] Q31[医药卫生—基础医学]