Serum interferon assay as a possible test for virus infections of man.

Acute phase serum gave positive results in an interferon assay when collected from 17 out of 45 (38 per cent) patients with proven virus infection, and from none of 43 patients with other disease and none of 61 healthy subjects. Sera from 11 of 43 (26 per cent) patients with suspected virus infection were also positive. Interferon was detected in the sera of volunteers infected with respiratory viruses in strict isolation. It is suggested that the test might be used to supplement conventional tests for virus infections, and with modification may provide a useful diagnostic aid.