Epidemiological evaluation of the protection conferred by the Nivgrip vaccine against influenza caused by the A(H3N2) virus.

The protection conferred by the inactivated influenza vaccine Nivgrip against influenza caused by the A(H3N2) virus was demonstrated in three school communities of a large urban centre during the epidemic outbreaks occurring in the winter season of 1983. The specific protection was reflected by the lower morbidity by influenza-like respiratory infections and by the absence or scarcity of postinfluenza complications in vaccinees.