[New strain-specific determinants in the hemagglutinins of influenza B viruses isolated in 1983-1984].

A comparative study of sensitivity to inhibitors and antigenic composition of hemagglutinins of influenza B virus strains isolated in the epidemic season of 1983-1984 and those circulating in 1940-1981 was carried out. The method of selective adsorption of highly active rabbit and rat sera demonstrated that hemagglutinins of contemporary influenza B viruses had both common cross-reacting determinants with previously circulating variants and qualitatively different, strain-specific ones. Among the variants isolated in 1983-1984, three subgroups of viruses were detected with different strain-specific hemagglutinin determinants.