[Analysis of the antigenic structure of influenza A/USSR/90/77 virus hemagglutinin].

Evolution of the antigenic structure of influenza virus hemagglutinin with the antigenic formula HA1 was studied by the determination of the capacity for interaction with monoclonal antibody and aminoacid substitutions in the protein. Consecutive changes in protein epitopes were found in isolates accumulating from the time of isolation of H1 influenza viruses in 1977.