Health-related behaviors and effectiveness of trivalent inactivated versus live attenuated influenza vaccine in preventing influenza-like illness among young adults.

BACKGROUND: Vaccination is the preferred preventive strategy against influenza. Though health behaviors are known to affect immunity and vaccine delivery modes utilize different immune processes, data regarding the preferred influenza vaccine type among adults endorsing specific health-related behaviors (alcohol use, tobacco use, and exercise level) are limited. METHODS: The relative effectiveness of two currently available influenza vaccines were compared for prevention of influenza-like illness during 2 well-matched influenza seasons (2006/2007, 2008/2009) among US military personnel aged 18-49 years. Relative vaccine effectiveness was compared between those self-reporting and not reporting recent smoking history and potential alcohol problem, and by exercise level using Cox proportional hazard modeling adjusted for sociodemographic and military factors, geographic area, and other health behaviors. RESULTS: 28,929 vaccination events and 3936 influenza-like illness events over both influenza seasons were studied. Of subjects, 27.5% were smokers, 7.7% had a potential alcohol-related problem, 10.5% reported minimal exercise, and 4.4% reported high exercise levels. Overall, the risk of influenza-like illness did not significantly differ between live attenuated and trivalent inactivated influenza vaccine recipients (hazard ratio, 0.98; 95% confidence interval, 0.90-1.06). In the final adjusted model, the relative effectiveness of the 2 vaccine types did not differ by smoking status (p = 0.10), alcohol status (p = 0.21), or activity level (p = 0.11). CONCLUSIONS: Live attenuated and trivalent inactivated influenza vaccines were similarly effective in preventing influenza-like illness among young adults and did not differ by health-related behavior status. Influenza vaccine efforts should continue to focus simply on delivering vaccine

Population Characteristics^a Among US Service Members, 18–49 Years of Age, During Two Influenza Seasons (2006/2007, 2008/2009).

<p>Abbreviations: ILI, influenza-like illness; IQR, interquartile range; LAIV, live, attenuated influenza vaccine; TIV, trivalent inactivated influenza vaccine.</p>a<p>Numbers (percentages) for all data except age, which is reported as median (IQR).</p

Risk of ILI by Vaccine Type and Health Behavior During Two Influenza Seasons (2006/2007, 2008/2009).

<p>Abbreviations: CI, confidence interval; HR, hazard ratio; ILI, influenza-like illness; LAIV, live, attenuated influenza vaccine; TIV, trivalent inactivated influenza vaccine.</p>a<p>Hazard ratio for each health behavior stratum is evaluated at the average level of other behaviors in the study population and adjusted for all other demographic covariates.</p

Univariable Hazard Risk Ratios for ILI Among US Service Members, 18–49 Years of Age, During 2006/2007 and 2008/2009 Influenza Seasons.

<p>Abbreviations: CI, confidence interval; HR, hazard ratio; ILI, influenza-like illness; LAIV, live, attenuated influenza vaccine; TIV, trivalent inactivated influenza vaccine.</p>a<p><i>p</i><0.05.</p

ICD-9 Codes Used To Identify Influenza-like Illness.

<p>ICD-9 Codes Used To Identify Influenza-like Illness.</p