2018年某小学连续2起流感暴发疫情中流感疫苗对甲型H3N2的保护效果分析

Analysis of protective effect of influenza vaccine against type A H3N2 in two consecutive Influenza outbreaks in a primary school in 2018

目的了解2018年北京市秋冬季接种的四价流感疫苗对甲型H3N2流感的保护效果。方法收集2018年12月北京市海淀区某小学连续发生的2起H3N2流感暴发疫情调查资料(含流感疫苗接种情况和实验室检测报告)的数据进行分析,计算保护率。结果 2起疫情罹患率分别为44. 63%(54/121)和25. 40%(32/126);H3N2核酸阳性率分别为77. 27%(34/44)和70. 83%(17/24),差异无统计学意义(χ2=0. 343,P=0. 558);流感疫苗对甲型H3N2亚型的保护率分别为12. 32%和-11. 35%,疫情1、2接种组和未接种组的发病率差别均无统计学意义(χ2=0. 204,P=0. 652;χ2<0. 001,P=1. 000)。结论2018年北京市秋冬季接种的四价流感疫苗对甲型H3N2亚型的保护效果不明显,流感防控不能完全依赖疫苗,还需多种形式的综合措施。

Objective To understand the protective effect of tetravalent influenza vaccine inoculated in autumn and winter of 2018 in Beijing on influenza A H3 N2.Methods Data of 2 successive H3 N2 influenza outbreaks in a primary school in Haidian District in December 2018(including influenza vaccination and laboratory test reports)were collected and analyzed to calculate the protection rate.Results The attack rate of 2 outbreaks was 44.63%(54/121)and 25.40%(32/126),respectively,and the positive rates of H3 N2 nucleic acid were 77.27%(34/44)and 70.83%(17/24),respectively.There was no significant difference between the 2 outbreaks(χ2=0.343,P=0.558).The protective rates of influenza vaccine against H3 N2 were 12.32%and-11.35%,respectively.There was no significant difference in the incidence of H3 N2 between the vaccination group and the non-vaccination group in outbreak 1 and 2(χ2=0.204,P=0.652;χ2<0.001,P=1.000).Conclusions The protective effect of tetravalent influenza vaccine inoculated in autumn and winter of 2018 in Beijing on influenza A H3 N2 is not obvious.Influenza prevention and control cannot rely entirely on vaccines,but also need a variety of comprehensive measures.