EMC virus infection in baboons as a model for studies on antiviral substances.

EMC virus causes a lethal infection in baboon monkeys within 4-8 days following subcutaneous injection with 10(4)-10(8) pfu of virus. The infection is accompanied by viremia, invasion of heart muscle and of brain. Monkeys infected with 10(6) pfu of EMC virus were treated with human leukocyte interferon. The interferon was injected intramuscularly first 0, 0.5, 6 and 24 h post-infection, then twice daily with a dose of 3 X 10(6) units for 5 consecutive days. All the monkeys treated with interferon remained alive and healthy. Animals infected with EMC virus, but not treated with interferon died within 6 days with evidence of myocarditis. The EMC virus-interferon interaction in baboon monkeys seems to provide a useful primate model system for testing the prophylactic and therapeutic antiviral activity of interferons or other antiviral substances.