Microneutralization assay(1) neuraminidase inhibition assay(1) pandemic influenza(1) H5N1 avian influenza virus(1) influenza vaccines(1) neuraminidase(1) reverse-genetics-derived virus(1) AS03 adjuvant(1) pandemic influenza A (H1N1) 2009 virus(1) influenza vaccine(1) Hemagglutination inhibition assay(1) frailty(1)