镇江地区诺如病毒分子流行病学特点及基因型分析

Molecular epidemiological characteristics and genotype analysis of norovirus in Zhenjiang region

目的分析2015-2016年镇江地区诺如病毒(No V)的分子流行病学特点及基因型分布。方法收集镇江地区腹泻患者粪便标本,逆转录PCR(RT-PCR)检测No V衣壳蛋白基因的表达水平,并对PCR产物行基因测序验证;Mega软件构建系统进化树,并进行序列进化和基因型分析。结果 No V总阳性率为5.30%(85/1 605),GⅠ组检出率为0.87%(14/1 605),GⅡ组检出率为4.55%(73/1 605),其中2份样本同时检出感染GⅠ/GⅡ。GⅡ组在10~20岁组中的阳性率最高(17.80%)。2015年No V的检出率以1月最高,11月、2月次之;2016年以12月最高,3月、4月次之。2015年No V的基因型以新GII.17型变异株为主(63.89%),2016年以GII.4 Sydney_2012株为主(35%)。结论镇江地区的No V以GII组为主,青少年患者阳性率高,主要流行季节为11月至次年4月,主要流行基因型为GII.17型变异株和GII.4 Sydney_2012株。

Objective To analyze the molecular epidemiological characteristics and genotype distribution of norovirus in Zhenjiang region during 2015 and 2016. Methods The fecal samples from diarrhea patients in Zhenjiang region were collected,and the expression level of norovirus capsid protein gene was detected by reverse transcription PCR（ RT-PCR）. The PCR products were validated by gene sequencing. Then,phylogenetic tree was constructed with Mega software,and sequence evolution and genotype were analyzed. Results The positive rate of norovirus infection was 5. 30%（ 85/1 605）. Among them,the detection rates of GⅠ genogroup and GⅡ genogroup were 0. 87%（ 14/1 605） and 4. 55%（ 73/1 605）,respectively,and 2 samples were detected both of G Ⅰ and G Ⅱ genogroups. The highest positive rate of GⅡ genogroup occurred in adolescent patients aged from 10 to 20 years（ 17. 80%）. During 2015,the detection rate of norovirus infection was the highest in January,and then in November and February. During 2016,the detection rate of norovirus infection was the highest in December,and then in March and April. The main genotypes of norovirus in 2015 and2016 were new GⅡ. 17 variant（ 63. 89%） and GⅡ. 4 Sydney_2012 strain（ 35%）,respectively. Conclusion The infection of norovirus in Zhenjiang region appears GⅡ as main genogroup,adolescent as main patients,November to April of the next year as main epidemic seasons,and GⅡ. 17 variant and GⅡ. 4 Sydney_2012 strain as main epidemic genotypes.