[Capacity of anti-influenza subunit vaccines to elicit the formation of heterologous antibodies].

The hemoagglutination-inhibiting antibody (h.i.a) response to A/Brazil/11/78 (H1 N1), A/Bangkok/1/79 (H3 N2) and B/Singapore/222/79 strains was evaluated in children and adults after administration of trivalent A/USSR/ 90/77 (H1 N1), A/Texas/1/77 (H3 N2), B/Hong Kong/8/73 influenza vaccines, two containing sub-unit and one whole virus. For each group of vaccinees, the behaviour of heterologous h.i.a. was compared to that of homologous antibodies. The rates of titer increases and the post-vaccinal geometric mean titers indicate that sub-unit vaccines are as immunogenic as whole virus vaccine in evoking heterologous antibodies. The greater difference between homologous and heterologous h.i.a. titers was found in adults for H3 N2 strains, the smaller for H1 N1 viruses. For the latter strains low post-vaccinal h.i.a. levels have been observed in all groups of vaccinees. In this regard the hypothesis has been put forward that immunogenicity of vaccines may be dependent on some intrinsic virus properties.