Detection of antibodies to strain-specific and cross-reactive antigenic determinants on the haemagglutinin of influenza viruses A/Texas/1/77 and A/Bangkok/1/79 in human sera. Brief report.

The antibody response to antigenic determinants on the haemagglutinin molecule of A/Texas/77 and A/Bangkok/79 strains was analysed by SRH of virus-absorbed sera, in human sera collected from persons of different ages following natural infection or immunization. The results have shown, as expected, low and high frequencies of strain-specific antibodies in sera of adults and young children respectively. However, in the latter group antibodies to cross-reactive antigens were also detected.