Antiviral Properties of Ehrlichin, an Antibiotic Produced by Streptomyces Lavendulae

Abstract
A preparation endowed with specific antiviral properties was obtained from culture filtrates of a non-streptothricin-producing strain of Streptomyces lavendulae. This preparation, designated Ehrlichin, was found to be inhibitory to influenza A and influenza B viruses in vitro with activity in vivo limited to influenza B virus. Concentrates of Ehrlichin were heat stable, non-dialyzable and resistant to tryptic digestion. Ehrlichin was inactive against representative species of bacteria, fungi, Chlamydozoaceae, pox viruses and bacterial viruses. Concentrates of Ehrlichin were found to be more effective in suppressing the formation of viral hemagglutinin when inoculated after rather than before infection of eggs with influenza B virus and exerted a slight but detectable suppressive effect on the degree of pulmonary consolidation in mice.