一起札如病毒引起社区暴发流行病学调查分析

An outbreak of acute gastroenteritis caused by Sapovirus in a community of Guangdong province

目的探讨一起由札如病毒引起的社区胃肠炎暴发的流行特征和临床发病情况,为开展疫情防控提供参考依据。方法采用回顾性研究方法对CT社区居民进行流行病学调查,以χ2检验比较罹患率的差异,采用RT-PCR方法对肛拭子、粪便和水样标本进行肠道病毒检测。结果该起疫情共发现422例病例,罹患率为11.95%。病例主要集中在21-24日,22日达到高峰,呈点源暴露特点,临床特征以呕吐和水样便为主。CT社区各村均有病例出现,以旧村罹患率最高(25.20%)。各年龄段均有病例发生,<25岁人群罹患率最高(16.41%),≥50岁次之(12.05%),25~49岁最低(8.42%)。病例肛拭子和粪便标本检测札如病毒阳性率为38.78%。采集24份水样的菌落总数、总大肠菌群和耐热大肠菌群合格率分别为95.83%、45.83%和50.00%,未检出札如病毒。结论本次疫情为一起由札如病毒感染引起的社区暴发事件,因集中式供水受污染而导致经水传播的可能性大。应完善感染性腹泻疾病监测体系,强化人群健康教育以及生活饮用水监测监督。

Objective To investigate the epidemiological characteristics and clinic symptoms of an outbreak of infectious diarrhea caused by Sapovirus,in CT community,Zhaoqing,Guangdong province.Methods Retrospective study of field epidemiology investigation was carried out and Chi-square test was used enteroviruses were detected by RT-PCR in swab,fecal specimens and water samples.Results A total of 422 cases were identified in this outbreak,with the prevalence as 11.95%.Cases mainly concentrated between 21 and 24,December,with curves noticed by point-source and peaked on the 22nd.Symptoms mainly appeared as vomiting,with watery stool.Patients were founded in every village,with the highest prevalence appeared in the elderly(25.20%)but involved in every age group.Sapovirus infection was most frequently seen in the population under 25 years of age,with overall prevalence as 16.41%.People older than 50 years of age took the second place(12.05%),and the lowest was seen between 25 to 49 years age group(8.42%).Sapovirus was detected in both swab and fecal specimens,with the positive rate as 38.78%.Both general and heat-resistant coliformed-bacteria were detected in the 24 monitored water samples,with the qualification rates as 95.83%,45.83%and 50.00%,respectively.However,Sapovirus was not detected in any of the water samples.Conclusions Our findings confirmed that an outbreak,caused by sapovirus infection in CT community was most likely related to the central water supply.The surveillance system for infectious diarrheal diseases should be improved and both public health awareness and surveillance programs on drinking water should be strengthened.