Mismatch between the 1997/1998 influenza vaccine and the major epidemic A(H3N2) virus strain as the cause of an inadequate vaccine‐induced antibody response to this strain in the elderly

摘要: The success of influenza vaccination depends largely on the antigenic match between vaccine strains and virus actually circulating during season. In past, this has proved to be satisfactory in most seasons. 1997/1998 season, however, hemagglutination inhibition (HI) assays with ferret antisera indicated a considerable mismatch H3N2 component prevalent epidemic A(H3N2) virus. results from analyses using pre- postvaccination serum samples volunteers various ages, including residents nursing homes who were more than 60 years age, good agreement obtained antisera. Homologous antibody responses as well cross-reactivity induced antibodies strain, declined increasing age vaccinees. As consequence these two effects, 84% vaccinees over 75 did not develop HI titers >/= 40 against major variant 1997/1998, suggesting that they protected infection variant. These findings support current policy World Health Organization (WHO), which is base worldwide surveillance predominantly by isolates tests. If an observed, protective efficacy vaccine, especially for elderly, may insufficient. observations also include elderly serologic trials.