Background. We report on a follow-up clinical and serological investigation of 274 children who received seasonal influenza vaccine (trivalent inactivated vaccine [TIV]) 1 year after receipt of either AS03B-adjuvanted subunit or whole virus monovalent A(H1N1)pdm09 vaccine and describe the antibody responses to the H3N2 A/Perth/16/2009 and B/Brisbane/60/2008 components of TIV.Methods. Vaccine responses were analyzed using hemagglutination inhibition (HAI) assays. In children aged <3 years, previous receipt of adjuvanted vaccine resulted in higher HAI antibody responses to H3N2 and B strains compared with nonadjuvanted vaccine (fold change 16.8 vs 4.3 for H3N2 and 7.0 vs 1.6 for B). In children aged >3 years, responses to the H3 and B components of TIV were similar between vaccine groups. Sera taken before and after the pandemic vaccine were also analyzed by HAI using A/Perth/16/2009 virus. This analysis showed that 11.1% of children receiving the AS03B-adjuvanted vaccine but only 1.4% in the nonadjuvanted group had a 4-fold rise to A/Perth/16/2009.Conclusion. AS03B-adjuvanted A(H1N1)pdm09 influenza vaccine generates a cross-reactive antibody response to H3N2 in children and enhances responses to heterologous subtypes in children aged <3 years 1 year later.
Bibliographical noteFunding Information:
Potential conflicts of interest. M. Z. and K. H. have been investigators of clinical trials sponsored by Novartis, Baxter, Sanofi Pasteur, and CSL Australia Ltd. A. J. P. acts as chief investigator for clinical trials on behalf of Oxford University; these trials are funded by vaccine manufacturers, and his institution receives unrestricted educational grants for conferences and seminars. A. J. P. does not receive any personal payments from industry. A. F. and S. N. F. undertake research, consultancy, and educational work for Sanofi Pasteur MSD (SPMSD), Novartis, GSK, Takeda, and Pfizer and for GSK, Pfizer, SPMSD, and Novartis, respectively. In 2006, K. H. has received financial assistance from SPMSD to attend a conference. S. N. F. has received financial assistance from GSK, Pfizer, and SPMSD to attend conferences. All grants and honoraria are paid into accounts of the respective employers (eg, NHS trusts, universities, health protection agencies) or to independent charities and none received personally. All other authors report no potential conflicts. All other authors have no conflicts of interest.
Financial support. The fieldwork was funded by the NIHR Health Technology Assessment program and the laboratory testing and analysis by the Health Protection Agency.
- Cross-reactive effects
- Oil-in-water adjuvant