Abstract
The capacliylrf egg-white to inhibit hemagglutination by swine influenza virus or formolized swine influenza vaccine is ascribed to a combination between an egg-white component and the virus or vaccine. This combination obstructs the agglutinative reaction of virus or vaccine with red blood cells. The virus is able to inactivate the egg-white inhibitor and, accordingly, the inhibition titer against virus is low. On the other hand, the vaccine combines more stably with inhibitor and the corresponding inhibition titer is high. Convalescent (anti-swine influenza) swine serum suppresses the inactivation of inhibitor by virus, indicating that the virus particles themselves are the active agents in the virus prepns. The results are interpreted in terms of an enzymatic hypothesis of virus function in the phenomenon.