Human seasonal Influenza A(H3N2) haemagglutination inhibition data 1990-2021 from the WHO Collaborating Centre for Reference and Research on Influenza, London, UK.

Haemagglutination inhibition (HI) assays performed on dates between 1990 and 2021 by the WHO Collaborating Centre for Reference and Research on Influenza, London, UK on viruses collected between 1961 and 2021. Dataset includes HI titres measured between 16,213 viruses and antisera raised against 381 reference viruses. It includes a total of 202,605 assay titres. These include 124,434 combinations of virus and reference virus if passage histories are ignored and 129,996 combinations accounting for differences in passage.