[Effectiveness of annual booster inoculations against various influenza serotypes and the procedure for mass vaccination]. / Izuchenie éffektivnosti ezhegodnykh, povtornykh privivok protiv grippa raznykh serotipov i taktika massovoi vaktsinatsii.

The epidemiological observation during an outbreak of A (H3N2) influenza in February-March, 1983, showed that the third annual vaccination with killed influenza vaccine did not enhance the effectiveness of vaccinations in the populations under study. It was observed that 14 months after immunization, 55.9% of the subjects examined had antibody titres of 1:40 or higher to the A/Bangkok/1/79 strain antigenically related to the vaccine strain, and 41% of the subjects of this group had antibodies to the subsequent drift variant of influenza A (H3N2) virus. These values were significantly higher than those in the group of subjects given no influenza vaccine. It is suggested that after 2 years of vaccination with killed influenza vaccines with the maximum coverage of the entire population, vaccinations be given alternately to half of previously vaccinated subjects with a 2-year interval up to the emergence of a new shift variant of influenza A virus, when again vaccination of the entire population for two successive years will be required.