The Household Influenza Vaccine Effectiveness Study: Lack of Antibody Response and Protection Following Receipt of 2014-2015 Influenza Vaccine.
Clin Infect Dis
; 65(10): 1644-1651, 2017 Oct 30.
Article
em En
| MEDLINE
| ID: mdl-29020179
ABSTRACT
BACKGROUND:
Antigenically drifted A(H3N2) viruses circulated extensively during the 2014-2015 influenza season. Vaccine effectiveness (VE) was low and not significant among outpatients but in a hospitalized population was 43%. At least one study paradoxically observed increased A(H3N2) infection among those vaccinated 3 consecutive years.METHODS:
We followed a cohort of 1341 individuals from 340 households. VE against laboratory-confirmed influenza was estimated. Hemagglutination-inhibition and neuraminidase-inhibition antibody titers were determined in subjects ≥13 years.RESULTS:
Influenza A(H3N2) was identified in 166 (12%) individuals and B(Yamagata) in 34 (2%). VE against A(H3N2) was -3% (95% confidence interval [CI] -55%, 32%) and similarly ineffective between age groups; increased risk of infection was not observed among those vaccinated in 2 or 3 previous years. VE against influenza B(Yamagata) was 57% (95% CI -3%, 82%) but only significantly protective in children <9 years (87% [95% CI 43%, 97%]). Less than 20% of older children and adults had ≥4-fold antibody titer rise against influenza A(H3N2) and B antigens following vaccination; responses were surprisingly similar for antigens included in the vaccine and those similar to circulating viruses. Antibody against A/Hong Kong/4801/14, similar to circulating 2014-2015 A(H3N2) viruses and included in the 2016-2017 vaccine, did not significantly predict protection.CONCLUSIONS:
Absence of VE against A(H3N2) was consistent with circulation of antigenically drifted viruses; however, generally limited antibody response following vaccination is concerning even in the context of antigenic mismatch. Although 2014-2015 vaccines were not effective in preventing A(H3N2) infection, no increased susceptibility was detected among the repeatedly vaccinated.Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Vírus da Influenza B
/
Vacinas contra Influenza
/
Influenza Humana
/
Vírus da Influenza A Subtipo H3N2
/
Anticorpos Antivirais
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article