Effect of Repeated Inoculation of Interferon Preparations on Infection of Mice with Encephalomyocarditis Virus

Administration of mouse brain interferon prior to or after inoculation of 100-250 LD50 of encephalomyocarditis (EMC) virus, conferred a significant degree of protection on weanling IC mice. Continuation of interferon treatment for several days after virial inoculation considerably increased the number of mice surviving infection. Most interferon protected mice did not develop HI antibody to EMC virus nor did they demonstrate resistance to viral rechallenge. By acting early in the course of viral infection interferon may have repressed viral multiplication below a level necessary to induce a specific immune response. Mice did not develop a “tolerance” to repeated inoculation of exogenous interferon. Considered together the experimental results suggested that continued interferon administration may prove of value in the treatment of some viral diseases.