title: Neutralizing Antibody Responses to Antigenically Drifted Influenza A(H3N2) Viruses among Children and Adolescents following 2014-2015 Inactivated and Live Attenuated Influenza Vaccination.
abstract: 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.
authors: Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, USA mwl2@cdc.gov.
authors: Min Z
authors: MZ
authors: Levine
authors: Department of Pediatrics, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania, USA.
authors: Judith M
authors: JM
authors: Martin
authors: Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, USA Battelle, Atlanta, Georgia, USA.
authors: F Liaini
authors: FL
authors: Gross
authors: Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
authors: Stacie
authors: S
authors: Jefferson
authors: Department of Immunology, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania, USA Center for Vaccine Research, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania, USA.
authors: Kelly Stefano
authors: KS
authors: Cole
authors: Center for Vaccine Research, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania, USA Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors: Crystal Ann
authors: CA
authors: Archibald
authors: Department of Family Medicine, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania, USA.
authors: Mary Patricia
authors: MP
authors: Nowalk
authors: Department of Family Medicine, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania, USA.
authors: Michael
authors: M
authors: Susick
authors: Department of Family Medicine, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania, USA.
authors: Krissy
authors: K
authors: Moehling
authors: Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, USA Atlanta Research and Education Foundation, Atlanta, Georgia, USA.
authors: Sarah
authors: S
authors: Spencer
authors: Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, USA Atlanta Research and Education Foundation, Atlanta, Georgia, USA.
authors: Jessie R
authors: JR
authors: Chung
authors: Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
authors: Brendan
authors: B
authors: Flannery
authors: Center for Vaccine Research, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania, USA Department of Family Medicine, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania, USA Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors: Richard K
authors: RK
authors: Zimmerman
mesh_terms: D000293:Adolescent; D057134:Antibodies, Neutralizing / Q000097:blood* / Q000276:immunology; D000914:Antibodies, Viral / Q000097:blood*; D000940:Antigenic Variation; D000956:Antigens, Viral / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D003429:Cross Reactions; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D053122:Influenza A Virus, H3N2 Subtype / Q000276:immunology*; D009981:Influenza B virus / Q000276:immunology; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000276:immunology*; D007251:Influenza, Human / Q000453:epidemiology / Q000276:immunology* / Q000517:prevention & control; D008297:Male; D012621:Seasons; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000276:immunology; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000276:immunology
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D000956:Antigens, Viral; D007252:Influenza Vaccines; D014613:Vaccines, Attenuated; D015164:Vaccines, Inactivated