河北省保定市一起水源性诺如病毒暴发疫情的流行特征及病原学研究

Epidemiological characteristics and etiological study of a water-borne outbreak of norovirus in Baoding city,Hebei province

目的:对河北省保定市一起水源性诺如病毒感染性腹泻暴发疫情进行调查分析,了解其流行特征,确定致病原。方法:开展现场流行病学调查,采集患者呕吐物、肛拭子或粪便标本,居民末梢水以及污水井井水标本,采用荧光定量PCR(real-time PCR)检测诺如病毒核酸,对阳性标本进行扩增并测序分析。结果:该小区发现病例70例,罹患率为2.33%。17份患者样本和6份水样经荧光定量PCR法检测均出现GI和/或GII核酸阳性。测序分析显示患者样本和污水井井水的诺如病毒都为GI.6和GII.2这两种基因型,序列同源性均高于98.8%。结论:本次疫情为一起由水源水污染导致的诺如病毒感染性胃肠炎暴发疫情,需加强对水源水的日常管理,定期消毒,广泛宣传,预防此类事件的发生。

Objective To investigate and analyze of a waterbom norovirus infectious diarrhea outbreak in Baoding,Hebei province,and to understand the epidemiological characteristics and to identify responsible pathogens.Methods Field epidemiological investigation was used.The samples of feces,vomit,anal swabs as well as tap water in the residents*home and water from sewage wells were used to detect norovirus nucleic acid by real-time reverse transcription polymerase chain reaction(Real-time PCR).Positive samples were amplified and sequenced.Results Seventy cases were found in the community with an attack rate of 2.33%.Real-time PCR results showed that 17 samples from patient and 6 water samples were positive for norovirus GI and/or GII.Sequencing analysis revealed that norovirus from both samples of patient and sewage belonged to norovirus GI.6 and GII.2 genotypes.The sequence similarity was higher than 98.8%.Conclusions The outbreak was identified as an outbreak of norovirus gastroentertitis caused by contamination of drinking water source.It is necessary to strengthen the daily management of water source,regular sterilization,wide-range publication to prevent the occurrence of such incidents.