上海市静安区水痘聚集性疫情中1剂次水痘减毒活疫苗保护效果观察

Effectiveness of one dose of varicella attenuated live vaccine in varicella outbreaks in Jing'an district,Shanghai

目的分析2013-2016年上海市静安区水痘聚集性疫情中儿童接种1剂次水痘减毒活疫苗(Varicella attenuated live vaccine,VarV)的保护效果(Vaccine effectiveness,VE)。方法收集2013-2016年静安区所有发生水痘聚集性疫情学校和托幼机构的儿童VarV接种和水痘发病信息,分析VarV的VE。结果在5 309名观察对象中,接种和未接种VarV者中的水痘病例分别占5.5%(252/4 586)、9.4%(68/723)。接种1剂次VarV的总VE为44.0%(95%CI:25.9%-57.7%);VE随接种年限延长而降低,接种满3年后VE下降明显,接种满8年后VE已无统计学意义。结论 1剂次VarV的VE较差,建议儿童在1岁和4岁进行2剂次VarV常规免疫。

Objective To analyze vaccine effectiveness （VE） of one dose of varicella attenuated live vac- cine （VarV） in varicella outbreaks during 2013-2016 in Jing＇an district of Shanghai. Methods We col- lected data on VarV vaccination and varicella cases among children during varicella outbreaks of schools and kindergartens in Jing＇ an from 2013 to 2016 to analyze VarV＇ s VE. Results In total, 5 309 children were surveyed; the proportion of varicella among vaccinated children and unvaccinated children were 5.5% （252/4 586） and 9. 4% （68/723） , respectively. The overall VE of one dose VarV was 44. 0% （95%CI： 25.9% -57.7% ）. VE decreased with increasing time since vaccination ; it decreased rapidly after 3 years, and was not statistically significantly different after 8 years. Conclusions VE of one dose VarV was not good. We recommend a 2-dose VarV vaccination schedule, given at 1 and 4 years of age.