一起诺如病毒感染聚集性疫情调查分析

Investigation and analysis of a norovirus outbreak

目的通过对疫情调查处置,分析疫情发生原因。方法对疫情发生的学校,开展现场流行病学调查,并采集部分患者肛拭子标本进行诺如病毒核酸检测。结果共14名学生发病,6例肛拭子标本诺如病毒GⅡ型核酸阳性,病例对照分析显示,学生周边1 m内是否有呕吐物的罹患水平(χ~2=11.67,P<0.05)、身边是否有患病学生的罹患水平(χ~2=7.47,P<0.05),差异均有统计学意义。结论该起聚集性疫情是由诺如病毒感染引起,近距离飞沫传播和吸入含有呕吐物的气溶胶可能是导致疫情播散的主要因素。

Objective Through the investigation and disposal of the epidemic,the causes of the outbreak were analyzed.Methods In the school where the epidemic occurred,field epidemiological investigation was carried out,and the anal swabs of some patients were collected for norovirus nucleic acid detection.Results A total of 14 students suffered from the disease,and 6 anal swab samples were positive for norovirus GⅡnucleic acid.Case comparison analysis showed that there were statistically significant differences in the norovirus infection rates of whether vomit were within 1 m around the students(χ~2=11.67,P<0.05),and in the norovirus infection rate of whether there were norovirus patients around the students(χ~2=7.47,P<0.05).Conclusion This aggregative epidemic was caused by norovirus infection,and the spread of the epidemic may be mainly caused by close-up droplets and inhalation of aerosols containing vomitus.