Inhibition of influenza a virus replication by rifampicin and selenocystamine

Abstract
The effects of selenocystamine, an inhibitor of influenza virus RNA‐dependent RNA polymerase in vitro activity, and the antibiotic rifampicin were studied on influenza A/PR/8/34 (HON1) infection in embryonated eggs. Both drugs completely inhibited hemagglutinating and infective virus yields when added at relatively early times postinfection. Maximal inhibition was produced by apparently noncytotoxic concentrations of 50 m̈g of selenocystamine, or of 400 m̈g of rifampicin, per egg.