Levine Min Z, Martin Judith M, Gross F Liaini, Jefferson Stacie, Cole Kelly Stefano, Archibald Crystal Ann, Nowalk Mary Patricia, Susick Michael, Moehling Krissy, Spencer Sarah, Chung Jessie R, Flannery Brendan, Zimmerman Richard K
Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
Department of Pediatrics, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania, USA.
Clin Vaccine Immunol. 2016 Oct 4;23(10):831-839. doi: 10.1128/CVI.00297-16. Print 2016 Oct.
Human influenza A(H3N2) viruses that predominated during the moderately severe 2014-2015 influenza season differed antigenically from the vaccine component, resulting in reduced vaccine effectiveness (VE). To examine antibody responses to 2014-2015 inactivated influenza vaccine (IIV) and live-attenuated influenza vaccine (LAIV) among children and adolescents, we collected sera before and after vaccination from 150 children aged 3 to 17 years enrolled at health care facilities. Hemagglutination inhibition (HI) assays were used to assess the antibody responses to vaccine strains. We evaluated cross-reactive antibody responses against two representative A(H3N2) viruses that had antigenically drifted from the A(H3N2) vaccine component using microneutralization (MN) assays. Postvaccination antibody titers to drifted A(H3N2) viruses were higher following receipt of IIV (MN geometric mean titers [GMTs], 63 to 68; 38 to 45% achieved seroconversion) versus LAIV (MN GMT, 22; only 3 to 5% achieved seroconversion). In 9- to 17-year-olds, the highest MN titers were observed among IIV-vaccinated individuals who had received LAIV in the previous season. Among all IIV recipients aged 3 to 17 years, the strongest predictor of antibody responses to the drifted viruses was the prevaccination titers to the vaccine strain. The results of our study suggest that in an antigenically drifted influenza season, vaccination still induced cross-reactive antibody responses to drifted circulating A(H3N2) viruses, although higher antibody titers may be required for protection. Antibody responses to drifted A(H3N2) viruses following vaccination were influenced by multiple factors, including vaccine type and preexisting immunity from prior exposure.
在2014 - 2015年中度严重流感季节占主导地位的甲型H3N2人流感病毒在抗原性上与疫苗成分不同，导致疫苗效力（VE）降低。为了检测儿童和青少年对2014 - 2015年灭活流感疫苗（IIV）和减毒活流感疫苗（LAIV）的抗体反应，我们从在医疗机构登记的150名3至17岁儿童中收集了接种疫苗前后的血清。采用血凝抑制（HI）试验评估对疫苗株的抗体反应。我们使用微量中和（MN）试验评估了针对两种已从甲型H3N2疫苗成分发生抗原漂移的代表性甲型H3N2病毒的交叉反应抗体反应。接种IIV后针对发生抗原漂移的甲型H3N2病毒的疫苗后抗体滴度更高（MN几何平均滴度[GMTs]，63至68；38至45%实现血清转化），而接种LAIV后（MN GMT，22；仅3至5%实现血清转化）。在9至17岁的儿童中，在上一季接种过LAIV的IIV接种者中观察到最高的MN滴度。在所有3至17岁的IIV接种者中，对发生抗原漂移病毒的抗体反应的最强预测因素是接种疫苗前对疫苗株的滴度。我们的研究结果表明，在抗原发生漂移的流感季节，尽管可能需要更高的抗体滴度来提供保护，但接种疫苗仍可诱导对正在传播的发生抗原漂移的甲型H3N2病毒产生交叉反应抗体反应。接种疫苗后对发生抗原漂移的甲型H3N2病毒的抗体反应受多种因素影响，包括疫苗类型和先前接触产生的预先免疫。
