2015年湖北地区诺如病毒流行特点及基因型别特征

Epidemic characteristics and genotypes of norovirus in Hubei Province,2015

目的了解湖北地区腹泻患者诺如病毒(norovirus,NV)的流行病学特征及基因型别特征。方法收集2015年1~12月儿童和成人腹泻患者的粪便标本687份,采用Real-time逆转录聚合酶链式反应(reverse transcription-polymerase chain reavtions,RT-PCR)方法进行NV的核酸检测;应用RT-PCR方法对NV检测阳性的GII型标本再行扩增ORF 2基因N/S区基因片段后,将该PCR产物直接测序并进行基因型别和系统发育分析。结果687份腹泻患者粪便标本中男性感染者93例,女性感染者56例,性别差异无统计学意义(x^2=1.193,P=0.275)。患者主要为5岁及以下儿童。2015年湖北地区NV感染全年均有发生,但流行高峰出现在9月份;NV主要为GII基因型,仅检出2例GI基因型。系统发育分析显示,NV GII流行株可分为5种基因亚型,分别为GII.17、GII.4 Sydney 2012、GII.3、GII.6和GII.13,不同基因亚型的流行呈现月份更替现象。结论 2015年湖北地区存在多种基因型NV的感染,加强NV的分子流行病学监测有利于NV的科学防控。

Objective To describe the epidemiologic characteristics and genotypes of norovirus（ NV） infection surveillance in Hubei Province in 2015. Methods 687 stool samples from children and adults with diarrhea were collected from January to December in 2015. NV was detected using real-time reverse transcription-polymerase chain reactions（ realtime RT-PCR）. Positive samples of NV GII were amplified to obtain the N/S region products by RT-PCR. The PCR products were sequenced for genotype identification and phylogenetic analysis. Results The infected male and female were 93 and 56 respectively and there was no significant difference between men and women（ χ^2= 1. 193,P = 0. 275）. The infected population was mainly under 5 years old. NV infections occurred through 2015 and the epidemic peak was in September. The main genotype of NV was GII in Hubei and only 2 strains was GI. The phylogenetic analysis showed that NV GII strains were identified as 5 subgenotypes,GII. 17,GII. 4 Sydney 2012,GII. 3,GII. 6 and GII. 13. The different genetic subtype predominated by months in turn. Conclusions There were various subgenotypes of NV among infected population in Hubei Province,2015. Enhancing the molecular epidemiological surveillance was crucial for NV scientific prevention.