show Abstracthide AbstractInfluenza A viruses continue to evolve at a high rate requiring continuous monitoring to understand their properties and maintain the efficacy of vaccines and antiviral drugs. We aimed to analyze the extent of interseasonal reassortment events among H3N2 influenza viruses and assess their potential contribution to the evolution of seasonal strains. We used next-generation sequencing to characterize the full genomes of more than100 human H3N2 influenza viruses isolated from 4 Asian countries (i.e. Japan, Myanmar, Vietnam, and Lebanon). We show evidence of frequent interseasonal reassortment events among H3N2 influenza viruses and report novel PB1-F2 and M2 gene polymorphisms conferring resistance to amantadine.