A SEARCH FOR VIRUS-INACTIVATING SUBSTANCES AMONG MICROORGANISMS.

One hundred and fifty organisms, comprising bacteria, fungi and actinomycetes, were isolated from straw-compost, manure, soil, drainage material and soil enriched with virus concentrates, and were tested for antiviral activity in vitro. Three of these organisms gave indications of possible inactivation of some of the fowl pox virus, and, in one case, of the laryngotracheitis virus. The active principle of one of these organisms was actinomycin A, an antibacterial substance known to be highly toxic to animals. The other two organisms were less extensively studied, and no claims regarding their antiviral potentialities can be made at present.