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. 2015 Oct 15;212(8):1200-8.
doi: 10.1093/infdis/jiv200. Epub 2015 Mar 27.

Does Influenza Vaccination Modify Influenza Severity? Data on Older Adults Hospitalized With Influenza During the 2012-2013 Season in the United States

Carmen S Arriola  1 , Evan J Anderson  2 , Joan Baumbach  3 , Nancy Bennett  4 , Susan Bohm  5 , Mary Hill  6 , Mary Lou Lindegren  7 , Krista Lung  8 , James Meek  9 , Elizabeth Mermel  10 , Lisa Miller  11 , Maya L Monroe  12 , Craig Morin  13 , Oluwakemi Oni  14 , Arthur Reingold  15 , William Schaffner  7 , Ann Thomas  16 , Shelley M Zansky  17 , Lyn Finelli  18 , Sandra S Chaves  18
Affiliations

Does Influenza Vaccination Modify Influenza Severity? Data on Older Adults Hospitalized With Influenza During the 2012-2013 Season in the United States

Carmen S Arriola et al. J Infect Dis. .

Abstract

Background: Some studies suggest that influenza vaccination might be protective against severe influenza outcomes in vaccinated persons who become infected. We used data from a large surveillance network to further investigate the effect of influenza vaccination on influenza severity in adults aged ≥50 years who were hospitalized with laboratory-confirmed influenza.

Methods: We analyzed influenza vaccination and influenza severity using Influenza Hospitalization Surveillance Network (FluSurv-NET) data for the 2012-2013 influenza season. Intensive care unit (ICU) admission, death, diagnosis of pneumonia, and hospital and ICU lengths of stay served as measures of disease severity. Data were analyzed by multivariable logistic regression, parametric survival models, and propensity score matching (PSM).

Results: Overall, no differences in severity were observed in the multivariable logistic regression model. Using PSM, adults aged 50-64 years (but not other age groups) who were vaccinated against influenza had a shorter length of ICU stay than those who were unvaccinated (hazard ratio for discharge, 1.84; 95% confidence interval, 1.12-3.01).

Conclusions: Our findings show a modest effect of influenza vaccination on disease severity. Analysis of data from seasons with different predominant strains and higher estimates of vaccine effectiveness are needed.

Keywords: adults; influenza; influenza vaccine; severe illness.

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Figures

Figure 1.
Figure 1.
Exclusion criteria and data-cleaning algorithm. Abbreviation: BMI, body mass index.
Figure 2.
Figure 2.
Kaplan–Meier estimates of length of stay in the intensive care unit (ICU), by vaccination status, for cases aged 50–64 years who were treated with antivirals.
See this image and copyright information in PMC

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References

    1. Zhou H, Thompson WW, Viboud CG, et al. Hospitalizations associated with influenza and respiratory syncytial virus in the United States, 1993–2008. Clin Infect Dis 2012; 54:1427–36. - PMC - PubMed
    1. Thompson M, Shay D, Zhou H, et al. Estimates of deaths associated with seasonal influenza—United States, 1976–-2007. MMWR Morb Mortal Wkly Rep 2010; 59:1057–62. - PubMed
    1. Centers for Disease Control and Prevention. Influenza activity—United States, 2012–13 season and composition of the 2013–14 influenza vaccine. MMWR Morb Mortal Wkly Rep 2013; 62:473–9. - PMC - PubMed
    1. Thompson WW, Shay DK, Weintraub E, et al. Mortality associated with influenza and respiratory syncytial virus in the United States. JAMA 2003; 289:179–86. - PubMed
    1. Ohmit SE, Thompson MG, Petrie JG, et al. Influenza vaccine effectiveness in the 2011–2012 season: protection against each circulating virus and the effect of prior vaccination on estimates. Clin Infect Dis 2014; 58:319–27. - PMC - PubMed

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