Influenza A(H1N1)2009 antibody seroprevalence in Scotland following the 2010/11 influenza season.

Following the 2010/11 influenza season, we determined the age- and location-specific seroprevalence of antibodies against the influenza A(H1N1)2009 virus in Scotland. Samples were analysed by microneutralisation assay. Age/seropositivity profiles varied significantly between cities. The increases in seroprevalence relative to the previous influenza season (2009/10) were similar across age groups and geographic locations. However, the increased seropositivity in older adults appeared to be driven by exposure to vaccination, indicating significantly lower levels of infection than in younger age groups.