The preventive effect of human interferon-alpha preparation on upper respiratory disease

Drops of a human leukocyte-derived interferon (HuIFN-alpha) preparation were instilled into the nasal cavity of 86 volunteers once a day from the beginning of December 1977 to the end of March 1978. The rise in hemagglutination-inhibition antibody titers against the three strains of influenza viruses was not significantly different between the interferon group and the control group. However, the rise in antibody titers against the parainfluenza virus, type 2, CA, was less in the interferon group than in the control group. There were fewer complaints of fever resulting from upper respiratory tract disease in the interferon group. Moreover, fevers higher than 39 degrees C were found only in placebo recipients. Fourteen of the 41 volunteers in the interferon group complained of subjective symptoms due to upper respiratory tract infection, whereas 28 of the 43 volunteers in the placebo group complained. This difference was significant. Thus our study indicates that prophylactic administration of an HuIFN-alpha-preparation can influence upper respiratory tract disease.