Impairment of human polymorphonuclear leucocyte function by influenza virus.

The effects of an influenza virus on polymorphonuclear leucocyte function were examined in vitro with a view to explaining why bacterial pneumonia often accompanies influenza in man. The ability of human polymorphonuclear leucocytes to show chemotaxis and to phagocytose staphylococci was inhibited when they were incubated with influenza viruses. Hexose-monophosphate-shunt activation was unaffected. The inhibitory effects were apparently specific to the virus.