2011年-2013年珠海市诺如病毒胃肠炎暴发的病毒分子流行病学分析

Viral molecular epidemiological analysis of norovirus gastroenteritis outbreaks in Zhuhai from 2011 to 2013

目的研究珠海市诺如病毒胃肠炎暴发的分子流行病学特征及流行株基因型的演化情况。方法收集珠海市2011年-2013年28起胃肠炎暴发疫情患者肛拭子标本619份,采用荧光逆转录聚合酶链反应(RT-PCR)定性检测诺如病毒RNA,按要求选取部分诺如病毒RNA阳性标本扩增诺如病毒衣壳蛋白,进行测序及同源性分析。结果其中17起疫情由诺如病毒感染引发,检测阳性率为19.55%(121/619);选取诺如病毒RNA阳性标本57份进行测序分型,成功分型的标本为47份,全部为No V GⅡ,14株为GⅡ.4型(其中5株为GⅡ.4 2006b,另外9株为GⅡ.4/Sydney_2012);12株属于GⅡ.3型;3株属于GⅡ.5型;18株属于GⅡ.6型。结论珠海市诺如病毒引起的食物中毒流行株属于GⅡ组,但基因亚型存在多样性,并且在短时间内造成多处暴发疫情,提示该状况将是今后防控监测的重点。

Objective To investigate the viral molecular epidemiological characteristics and the gene evolution pattern of epidemic strains of norovirus gastroenteritis outbreaks in Zhuhai from 2011 to 2013. Methods Anal swabs specimens were collected from 619 patients in 28 outbreaks of acute gastroenteritis from 2011 to 2013 in Zhuhai. Norovirus RNA was detected by real- time reverse transcription PCR. Partial positive norovirus specimens were selected to amplify the norovirus capsid protein for sequencing and homology analysis. Results 17 of 28 outbreaks were caused by norovirus with the positive rate of 19. 55%（ 121 /619）. 57 norovirus with positive RNA were selected to sequence and analyze,but 47 specimens which were successful genotyped belonged to norovirus genogroup Ⅱ. While 14 strains belonged to GⅡ. 4（ 5 strains belonged to GⅡ. 4 2006 b and 9strains belonged to GⅡ. 4 / Sydney_2012）,12 strains belonged to GⅡ. 3,3 strains belonged to GⅡ. 5,18 strains belonged to GⅡ. 6. Conclusion The prevalence strain causing food poison belongs to Norovirus genogroup Ⅱ in Zhuhai,but the subtypes were widely distributed. Epidemic strains resulted in a number of outbreaks in a short time,which is still the focus of the prevention and control as well as monitoring.