Comparative anti-influenza vaccination of some groups of the population with vaccines differing in virus purification level.

A total of 1215 persons, divided into 4 groups, were immunized with influenza vaccines A (highly purified, whole-virion), B (subunit, containing H and M), and C (conventional, commercial partly purified by Sharplers centrifugation). Post-vaccination reactions were followed, and serological tests (HI and NI) were performed with serum specimens taken from each vaccine 4 times during and after the vaccination period. The results point to clear superiority of purified and subunit vaccines over the conventional one.