Inhibition of the Growth of Viruses in the Chick Embryo by Aromatic Diamidines

Summary Inhibitory effects of aromatic diamidines on the viruses of influenza, mumps, feline pneumonitis and meningopneumonitis in the allantoic sac of chick embryos are compared. With pentamidine the order of activity may be stated as follows: feline pneumonitis > meningopneumonitis > mumps > influenza B > influenza A. Stilbamidine was inhibitory only to the mumps virus. Growth of influenza viruses in de-embryonated allantoic sac preparations was slowed down by propamidine and pentamidine. In mice the agents of feline pneumonitis and meningopneumonitis were inhibited to a slight degree, while results with influenza were negative.