Evidence is presented which indicates that certain polysaccharide preparations derived from various bacterial species, as well as similar materials not of bacterial origin, are capable of lessening the severity of infection with pneumonia virus of mice (PVM) and inhibiting multiplication of the virus in mouse lungs infected with this agent. It seems probable that modification with respect to the virus is mediated by a substance which may be polysaccharide in nature.

This content is only available as a PDF.