2015年合肥市诺如病毒聚集性疫情流行特征

Epidemic characteristics of norovirus outbreaks in Hefei City in 2015

目的通过分析2015年合肥市诺如病毒聚集性疫情流行特征,为制定预防诺如病毒感染的策略提供依据。方法采用描述流行病学方法分析2015年合肥市报告的诺如病毒疫情和个案资料。结果 2015年合肥市共发生诺如病毒聚集性疫情13起,波及845人,发病150例,总罹患率为17.75%。61.54%的疫情发生在3和10月份。发生的地点主要是幼儿园和学校等集体单位,占总疫情数的76.92%。119例(79.33%)患者出现呕吐症状,是诺如病毒患者的主要症状,腹泻和发热分别为37例(24.67%)和23例(15.33%),呕吐和发热症状随着年龄的增长呈下降趋势(χ2=7.50,P<0.05;χ2=4.92,P<0.05),而腹泻症状则随着年龄的增长呈增加趋势(χ2=9.98,P<0.05)。经食物传播是主要的感染途径。结论诺如病毒是合肥市腹泻病疫情重要病原体之一,应根据诺如病毒聚集性疫情特征加强学校等集体单位的监测和防控工作。

[Objective]To provide evidences for developing the prevention and treatment strategies of norovirus through analyzing epidemiologic characteristics of which outbreaks in Hefei City in 2015. [Methods]Descriptive epidemiological method was used to analyze the data of norovirus outbreaks and cases in Hefei City in 2015. [Results]A total of 13 norovirus outbreaks were reported in Hefei City in 2015,involving 845 people and 150 cases,and the overall attack rate was 17.75 %. 61.54% of the outbreaks were reported in March and October,while 76.92% of the outbreaks occurred in school and nursery institute. 119（79.33%）patients had vomiting and which was the main symptoms of norovirus infection,and diarrhea and fever developed in 37cases（24.67%）and 23 cases（15.33%）respectively. The rates of vomiting and fever declined with age（χ2=7.50,P〈0.05;χ2=4.92,P〈0.05）,while the rate of diarrhea increased with age（χ2=9.98,P〈0.05）. Food-borne infection was the major route.[Conclusion]Norovirus is the prominent pathogen of viral diarrhea in Hefei City. It is necessary to strengthen the surveillance and prevention of norovirus infection in schools and other collective units according to the epidemic characteristics of norovirus outbreaks.