Article

Cross-reactive Antibody Response to the Pandemic A (H1N1) 2009 Influenza Virus induced by vaccination with a seasonal trivalent influenza vaccine: A Longitudinal Study of Three Influenza Seasons in Japan.

The Chemo-Sero-Therapeutic Research Institute (Kaketsuken), Headquarters, Kumamoto 860-8568, Japan The Chemo-Sero-Therapeutic Research Institute (Kaketsuken), Kikuchi Research Center, Kumamoto 869-1298, Japan Statcom Company Limited, Tokyo 113-0034, Japan.
Microbiology and Immunology (Impact Factor: 1.31). 09/2012; 56(12). DOI: 10.1111/j.1348-0421.2012.00511.x
Source: PubMed

ABSTRACT The cross-reactivity of antibody to the swine-origin pandemic influenza A (H1N1) 2009 virus induced by vaccination with a seasonal trivalent influenza vaccine was studied. Paired sera from a cohort of adult volunteers vaccinated with a trivalent seasonal influenza vaccine every year from 2006 to 2008 were collected each year and tested by hemagglutination inhibition (HI) for antibody against the pandemic influenza A (H1N1) 2009 virus. There was little increase in the geometric mean titer overall; a slight increase was detected in the sera obtained in the 2007-2008 season but not in the other two seasons. The proportion of individuals with HI antibody titer ≥1:40 did not change significantly from year to year. These results indicated that cross-reactivity of the antibodies induced by a trivalent seasonal vaccine to the pandemic influenza A (H1N1) 2009 virus is marginal.

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