Objective: To evaluate the effectiveness of live attenuated influenza vaccine (LAIV) in the prevention of seasonal influenza in children aged 2-17 years. Methods: Literature retrieval of case-control studies on the effectiveness of LAIV against seasonal influenza in children published from January 2003 to November 2018 was conducted through Web of Science, PubMed, and ScienceDirect databases. The Stata 13.1 software was used for Meta-analysis. Results: A total of 14 studies were included in this study, and all were test-negative design (TND) studies. Our Meta-analysis showed that the effectiveness of LAIV in children was 49% (95%CI: 40%-57%). Subgroup analysis found that the protection rate of LAIV was 35% against influenza A (H1N1) pdm09 (95%CI: 5%-56%), 35% against influenza A (H3N2) (95%CI: 21%-46%), and 71% against influenza B (95%CI: 55%-82%). The protection rates of trivalent LAIV and quadrivalent LAIV in children were 56% (95%CI: 48%-63%) and 44% (95%CI: 27%-57%), respectively. The protection rates of LAIV in Europe and North America were 65% (95%CI: 47%-77%) and 46% (95%CI: 36%-55%), respectively. Conclusion: LAIV has a certain preventive effect on seasonal influenza in children aged 2-17 years.
目的： 评价流感减毒活疫苗（LAIV）预防2~17岁儿童季节性流感的保护效果。 方法： 通过Web of Science、PubMed和ScienceDirect数据库，检索2003年1月至2018年11月期间发表的、研究设计为病例对照的、关于研究LAIV预防儿童季节性流感保护效果的相关文献，采用Stata 13.1软件对纳入文献进行Meta分析。 结果： 共纳入文献14篇，均为检测阴性设计（Test-negative design，TND）研究。结果显示LAIV预防儿童季节性流感的保护效果为49%（95%CI：40%~57%）。亚组分析发现：LAIV预防A（H1N1）pdm09型、A（H3N2）型和B型流感的保护效果分别为35%（95%CI：5%~56%）、35%（95%CI：21%~46%）和71%（95%CI：55%~82%）；三价LAIV和四价LAIV在儿童中的保护效果分别为56%（95%CI：48%~63%）和44%（95%CI：27%~57%）；LAIV在欧洲地区和北美洲地区的保护效果分别为65%（95%CI：47%~77%）和46%（95%CI：36%~55%）。 结论： LAIV对2~17岁儿童季节性流感具有一定的预防作用。.
Keywords: Children; Live attenuated influenza vaccine; Meta-analysis; Seasonal influenza; Vaccine effectiveness.