Influenza is a very serious disease, which causes thousands of deaths all over the world every year. As there is so far no sufficiently effective causal therapy of influenza the main function of vaccination lies in prevention. Influenza is a major problem especially in collective facilities. Therefore, great emphasis is laid in the Czech Republic Army on the vaccination of military groups and on the evaluation of reactogenicity and immunogenicity of the vaccines used. The specific aim of the clinical trial was to evaluate the reactogenicity and immunogenicity of two inactivated split influenza vaccines Fluarix and Vaxigrip in healthy adult volunteers aged 18 – 60 years with stress on military groups. The study was designed as an open clinical trial with 2 groups each of 100 volunteers in one centre. Randomisation was not conducted so that each group received only the vaccine specified beforehand. Both the inactivated split vaccines evaluated, Vaxigrip and Fluarix are highly immunogenic both against declared and other antigenic variants of influenza. The study has demonstrated a favourable trend in the preparation of influenza vaccines towards a marked reduction of general solicited symptoms as compared with previous years. Despite minute differences in immunogenicity and reactogenicity, the vaccines are generally speaking comparable, and in healthy individuals aged 18 – 60 years they induce a sufficient protection against the onset and development of influenza. The results of our open clinical trial (without randomisation) have again proved that both manufacturers produce vaccines of a high European standard.

        Key words: influenza, vaccination, clinical trial, immunogenicity, reactogenicity