一起学校乙型流感暴发的流行病学分析

The epidemiological analysis of a influenza B outbreak at school

目的:通过分析某校乙型流感暴发事件,探索乙型流感暴发的自然规律与特点。方法:采用描述性流行病学方法,用SPSS软件进行统计分析。结果:疫情第6天病例数快速上升,第9天达到最高峰,第14天回到低位,末例在第23天;班级间罹患率比较,差别有统计学意义;咽拭子乙型流感病毒检测,体温≥38℃者阳性率为70%;血清乙型流感IgM抗体检测,体温≥38℃的患者阳性率为90%,体温38℃以下患者阳性率70%,无症状学生阳性率20%。结论:乙型流感暴发流行时间曲线为暴发前期需要2个最长潜伏期,暴发期和后期均需要3个最长潜伏期;血清乙型流感IgM抗体与病例体温高低成正相关。

Objective：Based on analysis of a school influenza B outbreak, the nature laws and characteristics of influenza B were explored. Methods： Descriptive epidemiological methods and SPSS software were involved in this study. Results： The epidemic cases increased suddenly on the sixth day, peaked on the ninth day, decreased on the fourth day, and the last case was found on the twenty- third day. The attack rates difference had no statistical sig- nificance among classes. In influenza B virus detection of throat swabs, the positive rate was 70% in cases with tem- perature above 38℃. In influenza B virus IgM antibody detection, the positive rates were 90% in cases with temper- ature above 38% and 70% in cases with temperature below 38℃, that of asymptomatic students was 20%. Conclu- sion： Tittle curve of itffluenza B epidemic outbeak showed two maximum incubation period before outbreak, three longest incubation period during and after outbreaks ; Serum influenza B IgM antibody and temperature were positive correlated.