Figure 3.

 Antibody responses induced by vaccination with AS03‐adjuvanted pandemic influenza and non‐adjuvanted seasonal influenza vaccines. Antibody levels before and after vaccination with Pandemrix and seasonal influenza vaccines were analyzed by HI test using several influenza A(H1N1)pdm09 strains isolated during the 2009–2010 (A) or 2010–2011 (B) epidemic seasons. Serum samples were collected at six time points as indicated in the figure. Geometric mean titers were calculated for each viral strain and the significance of difference between post‐vaccination samples at day 21 and at day 365 were calculated using Student’s paired, two‐tailed t‐test. Statistically significant difference (P < 0·01) was observed to all viral strains.