The Effect of Proflavine on the Growth of Viruses in the Chick Embryo

Abstract
Proflavine, when injected a few hours before or after the inoculation of virus, inhibits the multiplication of Type B strains of influenza virus in embryonated eggs, but does not influence the growth of Type A strains. The drug interferes also with the multiplication of vaccinia virus on the chorioallantois of the chick embryo when injected 2 hours following the virus. The growth of mumps and Newcastle disease viruses is unaffected by concentrations of proflavine active against vaccinia virus and Type B strains of influenza virus. In concentrations found to inhibit viral growth, proflavine is not virucidal, and it does not inhibit hemagglutination by any of these viruses.