Purified viral neuraminidase vaccine to control influenza.

The control of influenza by immunoprophylaxis is difficult because of the antigenic mutability of the influenza virus and the unpredictability of its epidemiologic behaviour. The inactivated whole-virus vaccine currently used is not ideal. Vaccination with pure neuraminidase is suggested. The induced antineuraminidase antibody will restrict viral invasion. Mild illness may or may not occur. On subsequent exposure to influenza virus the individual will produce antihemagglutinin and antineuraminidase antibodies and will be resistant to both infection and illness. Since antigenic changes are less frequent in the viral neuraminidase than in the viral hemagglutinin, the vaccine would be usable for longer periods than the presently used inactivated whole-virus vaccine.