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: 1.24). 09/2012; 56(12). DOI: 10.1111/j.1348-0421.2012.00511.x
Source: PubMed


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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    ABSTRACT: Population-based febrile respiratory illness surveillance conducted by the Department of Defense contributes to an estimate of vaccine effectiveness. Between January and March 2011, 64 cases of 2009 A/H1N1 (pH1N1), including one fatality, were confirmed in immunized recruits at Fort Jackson, South Carolina, suggesting insufficient efficacy for the pH1N1 component of the live attenuated influenza vaccine (LAIV). To test serologic protection, serum samples were collected at least 30 days post-vaccination from recruits at Fort Jackson (LAIV), Parris Island (LAIV and trivalent inactivated vaccine [TIV]) at Cape May, New Jersey (TIV) and responses measured against pre-vaccination sera. A subset of 78 LAIV and 64 TIV sera pairs from recruits who reported neither influenza vaccination in the prior year nor fever during training were tested by microneutralization (MN) and hemagglutination inhibition (HI) assays. MN results demonstrated that seroconversion in paired sera was greater in those who received TIV versus LAIV (74% and 37%). Additionally, the fold change associated with TIV vaccination was significantly different between circulating (2011) versus the vaccine strain (2009) of pH1N1 viruses (ANOVA p value = 0.0006). HI analyses revealed similar trends. Surface plasmon resonance (SPR) analysis revealed that the quantity, IgG/IgM ratios, and affinity of anti-HA antibodies were significantly greater in TIV vaccinees. Finally, sequence analysis of the HA1 gene in concurrent circulating 2011 pH1N1 isolates from Fort Jackson exhibited modest amino acid divergence from the vaccine strain. Among military recruits in 2011, serum antibody response differed by vaccine type (LAIV vs. TIV) and pH1N1 virus year (2009 vs. 2011). We hypothesize that antigen drift in circulating pH1N1 viruses contributed to reduce vaccine effectiveness at Fort Jackson. Our findings have wider implications regarding vaccine protection from circulating pH1N1 viruses in 2011-2012.
    Full-text · Article · Apr 2012 · PLoS ONE
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    Full-text · Article · Jun 2013 · British Journal of General Practice