2016-2017年哈尔滨市诺如病毒感染暴发疫情流行特征分析

Epidemiologic characteristics of norovirus outbreaks in Harbin, 2016-2017

目的 了解哈尔滨市诺如病毒感染暴发的流行特征.方法 收集2016年1月至2017年12月哈尔滨市诺如病毒暴发疫情流行病学调查个案、调查报告及实验室检测资料,对疫情发生的三间分布、病例临床表现及传播途径等进行统计分析.结果 2016-2017年哈尔滨市累计报告疫情13起,总罹患率为3.6％（421/11 654）,病原体以诺如病毒GⅡ型为主.疫情全部发生在学校,病例均为学生,最小年龄为3岁,最大年龄为23岁,平均年龄（13.7±3.1）岁.学龄前儿童罹患率最高,为18.3％（102/557）;其次为小学生（8.8％,208/2 376）与大中专院校学生（1.3％,111/8 721）,差异有统计学意义（x2=663.17,P＜0.01）.5至6月出现一个小高峰,发生疫情8起,病例占57.2％（241/421）,传播途径主要为人与人传播.结论 诺如病毒感染疫情主要发生在学校、托幼等集体机构,在高发季节对高发场所加强监测,可有效控制疫情的发生和蔓延.

Objective To understand the epidemiologic characteristics of norovirus outbreaks in Harbin during 2016-2017.Methods Epidemiologic cases reports,investigation reports and laboratory tests of the norovirus outbreaks between Jan.,2016 and Dec.,2017 were collected and the spatial,temporal and population distributions,clinical features and routes of transmission were analyzed.Results A total of 13 norovirus outbreaks were reported during this period.The overall attack rate was 3.6％ （421/11 654）.All the outbreaks occurred in schools and all cases were students.The minimum age was 3 years old,the maximum was 23 years old,and the average age was （13.7±3.1） years old.Preschoolers had the highest rate,namely 18.3％ （102/557）,followed by primary school students （8.8％,208/2 376） and college students （1.3％,111/8 721）.The difference was statistically significant （x2=663.17,P＜0.01）.There was a small peak from May to June,including of eight outbreaks and 57.2％ （241/421） of cases.The main transrmission route was human-to-human.Conclusions Norovincs outbreaks occured in schools and kindergartens.The surveillance for norovirus infection during peak time should be strengthened in schools and kindergartens for effective controlling of epidemics and disease spreading.