Comparative Study on Antigenicity Variation of Influenca Virus in Recent Years

Objective To study the antigenicity variation of influenza virus.Methods Perform cross hemagglutination inhibition test on the standard antigens of influenza virus strains A1,A3 and B epidemic since 2000 with the corresponding immunosera.Calculate the antigenic ratio using the obtained data and analyze the variation of antigenicity.Results The antigenic ratios of two A1 strains,four A3 strains and five B strains were 2.6,1.2-13.2 and 1.8-22.6 respectively.Conclusion Both A1 and A3 strains showed no significant variation in their antigenicties,however,the antigenicity of B strain showed significant variation.