某高校1起诺如病毒感染性腹泻暴发疫情调查

Investigation on an outbreak of Norovirus diarrhea in a university,Yancheng city

目的 目的 调查某高校感染性腹泻暴发疫情,查找病原和传播危险因素,为采取针对性防控措施扑灭疫情提供依据。方法 采集病例、食堂从业人员及环境有关标本,进行可疑病原体核酸检测。采用现场卫生学调查和病例对照研究方法分析可能传播因素,并采取措施控制疫情。结果 全校共发现病例83例,罹患率为1.79%。学生病例82例,食堂工人1例,罹患率分别为1.95%和0.24%。疫情自2015年12月9日始发至2016年1月6日终止,持续36d,期间出现几个不规则流行峰,其中12月21~22日发病较多。学生病例宿舍楼间有明显聚集性,病例对照研究显示接触病例、饭前不经常洗手、便后不经常洗手是引起诺如病毒的感染的危险因素。3例病人和1名食堂从业人员检测GⅠ型诺如病毒阳性,病人呕吐物及环境标本均阴性。结论 该疫情为1起诺如病毒GⅠ型引起的感染性腹泻暴发疫情,疫情持续时间长,可能的传播因素为密切接触,导致疫情的扩散蔓延。

Objective To investigate an outbreak of infectious diarrhea in a university,so as to provide basis for targeted prevention and control measures. Methods Specimens were collected from the cases, canteen workers, and environment to be tested for suspected pathogen nucleic acid PCR,and analyze the risk factors of infection with field hygienic survey and case control study methods,and measures were taken to control the outbreak. Results A total of 83 cases were detected,the attack rate was 1.79%. 82 were students （attack rate：1. 95%）,1 case was teacher （attack rate：0.24%）. The outbreak lasted for 27 days from December 9th, 2015 to January 6th, 2016. During the outbreak, several irregular peaks appeared,most cases occurred during December 21-22. Cases between dormitories of students had obvious aggregation, casecontrol study showed that exposure to eases, no washing hands before meals and after using the toilet were the risk factors for this Norovirus infection. 3 cases of patients, 1 canteen worker were tested positive for Norovirus type G I ,and patient vomit and environmental samples were negative. Conclusion Norovirus is confirmed as the cause to this infectious diarrhea outbreak,which may be transmitted by close contact leading to the spread of the outbreak.