[Homologous and heterologous antibody response induced in man by anti-influenza vaccine containing A/England/42/72 and b/Massachusetts/71].

In november 1973, 43 subjects living in a home for aged were given one dose of influenza vaccine, containing A/England/42/72 and B/Massachusetts/71. After 4 and 20 weeks, sera were tested for antibody contentto the homologous and to A/port Chalmers/1/73 viruses by haemoagglutination inhibition technique. Control group included 23 untreated subjects. The satisfactory increase in the anti-A/England/42/72 antibodies induced by vaccine indicated a good antigenic potency of the A component. The satisfactory cross-reacting response suggests that the "drift" in antigenic content between A England/42/72 and A/Port Chalmers/1/73 was moderate. On the contrary the increase in anti-B/Massachusetts/71 antibodies after vaccination was observed only in a limited number of cases. Twelve subjects (9 treated and 3 controls) experienced upper respiratory tract infections which appeared to be not related to infuenza viruses.