Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2015 Jun 12;33(26):3003-9.
doi: 10.1016/j.vaccine.2015.02.042. Epub 2015 Mar 23.

Deaths averted by influenza vaccination in the U.S. during the seasons 2005/06 through 2013/14

Ivo M Foppa  1 , Po-Yung Cheng  2 , Sue B Reynolds  3 , David K Shay  4 , Cristina Carias  5 , Joseph S Bresee  4 , Inkyu K Kim  2 , Manoj Gambhir  6 , Alicia M Fry  4
Affiliations

Deaths averted by influenza vaccination in the U.S. during the seasons 2005/06 through 2013/14

Ivo M Foppa et al. Vaccine. .

Abstract

Background: Excess mortality due to seasonal influenza is substantial, yet quantitative estimates of the benefit of annual vaccination programs on influenza-associated mortality are lacking.

Methods: We estimated the numbers of deaths averted by vaccination in four age groups (0.5 to 4, 5 to 19, 20 to 64 and ≥65 yrs.) for the nine influenza seasons from 2005/6 through 2013/14. These estimates were obtained using a Monte Carlo approach applied to weekly U.S. age group-specific estimates of influenza-associated excess mortality, monthly vaccination coverage estimates and summary seasonal influenza vaccine effectiveness estimates to obtain estimates of the number of deaths averted by vaccination. The estimates are conservative as they do not include indirect vaccination effects.

Results: From August, 2005 through June, 2014, we estimated that 40,127 (95% confidence interval [CI] 25,694 to 59,210) deaths were averted by influenza vaccination. We found that of all studied seasons the most deaths were averted by influenza vaccination during the 2012/13 season (9398; 95% CI 2,386 to 19,897) and the fewest during the 2009/10 pandemic (222; 95% CI 79 to 347). Of all influenza-associated deaths averted, 88.9% (95% CI 83 to 92.5%) were in people ≥65 yrs. old.

Conclusions: The estimated number of deaths averted by the US annual influenza vaccination program is considerable, especially among elderly adults and even when vaccine effectiveness is modest, such as in the 2012/13 season. As indirect effects ("herd immunity") of vaccination are ignored, these estimates represent lower bound estimates and are thus conservative given valid excess mortality estimates.

Keywords: Averted deaths; Bayesian analysis; Influenza; Influenza vaccine; Influenza-associated mortality; Monte Carlo simulation.

PubMed Disclaimer

Figures

Fig. 1
Fig. 1
The number of influenza-like illness (ILI) visits reported by provider (ILI relative) and the number of specimens testing positive for influenza A(H1N1), A(H3N2), A(H1N1) pdm09 and B viruses, October, 2005 through July, 2014.
Fig. 2
Fig. 2
The median number of deaths associated with influenza (excess mortality = EM) and the indicators for influenza A(H1N1), A(H3N2), A(H1N1) pdm09 and B viruses, October, 2005 through July, 2014.
See this image and copyright information in PMC

References

    1. Thompson WW, Moore MR, Weintraub E, Cheng PY, Jin X, Bridges CB, et al. Estimating influenza-associated deaths in the United States. Am J Public Health. 2009;99(Suppl 2):S225–S230. - PMC - PubMed
    1. Foppa IM, Hossain MM. Revised estimates of influenza-associated excess mortality, United States, 1995 through 2005. Emerg Themes Epidemiol. 2008;5:26. - PMC - PubMed
    1. Thompson WW, Shay DK, Weintraub E, Brammer L, Cox N, Anderson LJ, et al. Mortality associated with influenza and respiratory syncytial virus in the United States. JAMA. 2003;289:179–186. - PubMed
    1. Burney LE. Influenza immunization: statement. Public Health Rep. 1960;75:944. - PMC - PubMed
    1. Fiore AE, Uyeki TM, Broder K, Finelli L, Euler GL, Singleton JA, et al. Morb Mortal Wkly Rep Recomm Rep. Vol. 59. Centers for Disease Control; 2010. Prevention and control of influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices (ACIP), 2010; p. 1. - PubMed

MeSH terms

Substances