title: Comparison of serum hemagglutinin and neuraminidase inhibition antibodies after 2010-2011 trivalent inactivated influenza vaccination in healthcare personnel.
abstract: Background.  Most inactivated influenza vaccines contain purified and standardized hemagglutinin (HA) and residual neuraminidase (NA) antigens. Vaccine-associated HA antibody responses (hemagglutination inhibition [HAI]) are well described, but less is known about the immune response to the NA. Methods.  Serum of 1349 healthcare personnel (HCP) electing or declining the 2010-2011 trivalent-inactivated influenza vaccine ([IIV3], containing A/California/7/2009 p(H1N1), A/Perth/16/2009 [H3N2], B/Brisbane/60/2008 strains) were tested for NA-inhibiting (NAI) antibody by a modified lectin-based assay using pseudotyped N1 and N2 influenza A viruses with an irrelevant (H5) HA. Neuraminidase-inhibiting and HAI antibody titers were evaluated approximately 30 days after vaccination and end-of-season for those with polymerase chain reaction (PCR)-confirmed influenza infection. Results.  In 916 HCP (68%) receiving IIV3, a 2-fold increase in N1 and N2 NAI antibody occurred in 63.7% and 47.3%, respectively. Smaller responses occurred in HCP age >50 years and those without prior 2009-2010 IIV3 nor monovalent A(H1N1)pdm09 influenza vaccinations. Forty-four PCR-confirmed influenza infections were observed, primarily affecting those with lower pre-exposure HAI and NAI antibodies. Higher pre-NAI titers correlated with shorter duration of illness for A(H1N1)pdm09 virus infections. Conclusions.  Trivalent-inactivated influenza vaccine is modestly immunogenic for N1 and N2 antigens in HCP. Vaccines eliciting robust NA immune responses may improve efficacy and reduce influenza-associated morbidity.
authors.affiliation: Division of Infectious Diseases.
authors.forename: Maryrose R
authors.initials: MR
authors.lastname: Laguio-Vila
authors.affiliation: Epidemiology and Prevention Branch , Influenza Division/National Center for Immunization and Respiratory Diseases/Centers for Disease Control and Prevention , Atlanta, Georgia.
authors.forename: Mark G
authors.initials: MG
authors.lastname: Thompson
authors.affiliation: Epidemiology and Prevention Branch , Influenza Division/National Center for Immunization and Respiratory Diseases/Centers for Disease Control and Prevention , Atlanta, Georgia.
authors.forename: Sue
authors.initials: S
authors.lastname: Reynolds
authors.affiliation: Epidemiology and Prevention Branch , Influenza Division/National Center for Immunization and Respiratory Diseases/Centers for Disease Control and Prevention , Atlanta, Georgia.
authors.forename: Sarah M
authors.initials: SM
authors.lastname: Spencer
authors.affiliation: Division of Pediatric Infectious Diseases , Baylor Scott and White Health , Temple, Texas.
authors.forename: Manjusha
authors.initials: M
authors.lastname: Gaglani
authors.affiliation: The Center for Health Research , Kaiser Permanente Northwest , Portland, Oregon.
authors.forename: Allison
authors.initials: A
authors.lastname: Naleway
authors.affiliation: Abt Associates , Cambridge Massachusetts.
authors.forename: Sarah
authors.initials: S
authors.lastname: Ball
authors.affiliation: Abt Associates , Cambridge Massachusetts.
authors.forename: Sam
authors.initials: S
authors.lastname: Bozeman
authors.affiliation: Department of Microbiology and Immunology , University of Rochester Medical Center , New York.
authors.forename: Steven
authors.initials: S
authors.lastname: Baker
authors.affiliation: Department of Microbiology and Immunology , University of Rochester Medical Center , New York.
authors.forename: Luis
authors.initials: L
authors.lastname: Martínez-Sobrido
authors.affiliation: Epidemiology and Prevention Branch , Influenza Division/National Center for Immunization and Respiratory Diseases/Centers for Disease Control and Prevention , Atlanta, Georgia.
authors.forename: Min
authors.initials: M
authors.lastname: Levine
authors.affiliation: Epidemiology and Prevention Branch , Influenza Division/National Center for Immunization and Respiratory Diseases/Centers for Disease Control and Prevention , Atlanta, Georgia.
authors.forename: Jackie
authors.initials: J
authors.lastname: Katz
authors.affiliation: Epidemiology and Prevention Branch , Influenza Division/National Center for Immunization and Respiratory Diseases/Centers for Disease Control and Prevention , Atlanta, Georgia.
authors.forename: Alicia M
authors.initials: AM
authors.lastname: Fry
authors.affiliation: Division of Infectious Diseases.
authors.forename: John J
authors.initials: JJ
authors.lastname: Treanor
keywords: antibody; hemagglutinin-inhibition; influenza; neuraminidase-inhibition; vaccine