Interferon and Resistance to Upper Respiratory Virus Illness

SummaryThe role of interferon in the common cold syndrome caused by Coxsackie virus A type 21 and by rhinovirus type 15 was evaluated in volunteers. Interferon appeared in nasal wash transiently and early enough during infection to have had a role in causing recovery from illness; it was not found in serum. The influence of one respiratory virus infection on a subsequent one was evaluated by challenging men with Coxsackie virus 4 weeks after a primary rhinovirus infection. Increasing severity of illness during primary rhinovirus infection was associated with decreasing severity of illness during secondary Coxsackie virus infection. No correlation existed between interferon titers in nasal wash during the two infections, but titers during secondary Coxsackie virus infection were less than those during primary Coxsackie virus infection in other volunteers. Interferon did not appear to account for the resistance to Coxsackie virus illness afforded by a preceding rhinovirus common cold.