Article

Association Between Seasonal Influenza Vaccination in 2008-2009 and Pandemic Influenza A (H1N1) 2009 Infection Among School Students From Kobe, Japan, April-June 2009

Field Epidemiology Training Program, National Institute of Infectious Diseases, Tokyo, Japan.
Clinical Infectious Diseases (Impact Factor: 9.42). 11/2011; 54(3):381-3. DOI: 10.1093/cid/cir787
Source: PubMed

ABSTRACT We assessed the effect of seasonal trivalent inactivated influenza vaccination (TIV) on pandemic influenza 2009 (pH1N1)-related illness from April to June 2009 among 2849 students (aged 12-18 years). TIV was associated with an increase in the frequency of pH1N1-related illness among subjects (adjusted odds ratio, 1.47; 95% confidence interval, 1.14-1.89). TIV during the 2008-2009 season increased the risk of pH1N1-related illness from April to June 2009.

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