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Tables and Figures
Table 1: HA gene analysis of AH1N1)pdm09 viruses. The proportion of novel HA variants in season 2019-2020 expressing cluster specific substitutions in HA1 and HA2 is indicated. Additionally, the proportion of viruses with reduced reactivity (>4-fold versus ≤4-fold) in the hemagglutination inhibition test is shown.