[Comparative evaluation of the reactogenicity and immunogenicity of inactivated influenza vaccines in the elderly]

A comparative study was carried out to assess reactogenicity and immunogenicity of inactivated influenza vaccines (Begrivac, Vaxigrip, Grippol, Influvac, and Fluarix), licensed in Russia. Immunization of the elderly demonstrated low reactogenicity and high immunogenicity for all vaccines. Concomitant chronic diseases had no influence on the vaccine immunogenicity levels, which testifies to the benefit of vaccination in this age group. In the group of vaccinated the highest seroconversion to all vaccine strains was found for Vaxigrip (82-89% for group A viruses and 86% for group B virus); the vaccine demonstrated the highest level of diagnostic increase of antibody titers to all 3 viruses, i.e. 69.0% (p < .05), with 22.0% of vaccinees gained antibodies to 2 vaccine viruses (91.0% in total). The number of positive responses to 3 and 2 strains in subjects immunized with Fluarix, Begrivac and Influvac reached 85.0%, 85.0% and 83.0% respectively. It is noteworthy that the combination of surface antigens of A and B flu viruses in low concentration with polyoxidonium immune modulator in Grippol induced intensive immune response.