Abstract
An influenza virus vaccine containing the purified surface haemagglutinin and neuraminidase antigens of A/Victoria/75 and B/Hong Kong/73 viruses adsorbed to an aluminium hydroxide gel was assessed for reactogenicity and immunogenicity in children aged 4 to 11 years, since there is no influenza virus vaccine available for this age group. Significant serum haemagglutination-inhibiting antibody responses to the A/Victoria/75 and B/Hong Kong/73 haemagglutinin antigens present in the vaccine were observed in 47% and 35%, respectively, of the children vaccinated, with a single dose. The vaccine induced no significant local or systemic reactions.