深圳市龙华区2019年札如病毒基因分型以及进化分析

Genotyping and evolutionary analysis of Sapovirus in Longhua District of Shenzhen in 2019

目的分析2019年深圳市龙华区札如病毒的基因型别,掌握辖区内札如病毒的流行情况。方法采用实时荧光定量PCR对283份龙华区感染性腹泻疫情样本进行轮状病毒、诺如病毒和札如病毒核酸检测,对札如病毒阳性样本核酸采用RT-PCR(反转录–聚合酶链式反应)扩增,并对扩增产物进行序列测定和遗传进化分析。结果 2019年龙华区共发生感染性腹泻聚集性疫情24起,共采集283份样本。其中由诺如病毒引起15起(占62.5%),札如病毒引起4起(占16.6%),札如和诺如病毒共同引起1起(占4.1%),未检测出病原体4起(占16.6%)。283份感染性腹泻疫情样本中,诺如病毒检测阳性率为17.7%(50/283);札如病毒阳性率为8.1%(23/283),轮状病毒未检出,所有病例无混合感染情况。23例札如阳性样本有5例VP1条带扩增成功,扩增效率为21.7%,基因亚型鉴定分析结果表明2株为GII.3型,3株为GII.4型。结论在2019年龙华区腹泻疫情方面,GⅡ.3和GⅡ.4型是札如病毒的主要型别。诺如依然是龙华区感染性腹泻中引起散发和暴发的首要病原体,星状,轮状,腺状仅在散发病例中发现,而札如已成为引起急性腹泻病的重要病原体,应尽快开展龙华区对札如病毒的常规检测和进一步的分子分型工作。

Objective To analyze the genotypes of Sapovirus in Longhua District in 2019,and to further understand the prevalence of Sapovirus in the area.Methods Totally 283 samples of infectious diarrhea in Longhua District were detected for Rotavirus,Norovirus and Sapovirus by real-time PCR,and then the positive samples of Sapovirus were amplified by RT-PCR(reverse transcription-polymerase chain reaction),and the amplified products were sequenced and analyzed for genetic evolution.Results In 2019,there were 24 outbreaks of infectious diarrhea in Longhua District,and 283 samples in total.Among the 24 outbreaks,15 cases(62.5%)were caused by Norovirus;4 cases(16.6%)were caused by Sapovirus;1 case(4.1%)was caused by both Sapovirus and Norovirus;4 cases(16.6%)were not detected pathogen.Among the 283 infectious diarrhea samples,50 were Norovirus,with a positive rate of 17.6%;23 were Sapovirus,with a positive rate of 8.1%;Rotavirus was not detected.There was no mixed infection in all samples.VP1 bands were amplified successfully in 5 of 23 Sapovirus positive samples,and the amplification efficiency was 21.7%.Genotyping analysis of the five positive samples showed that two strains were GⅡ.3 and three strains were GⅡ.4.Conclusion GⅡ.3 and GⅡ.4 are the main genotypes of Sapovirus in the diarrhea epidemic of Longhua District in 2019.Norovirus is still the main pathogen causing sporadic and outbreak of infectious diarrhea in our district.Astrovirus,Rotavirus and Adenovirus are only found in sporadic cases.Sapovirus has become an important pathogen causing acute diarrhea.Routine detection and further molecular typing of Sapovirus should be carried out in Longhua District as soon as possible.