Circulating Interferon after Measles Vaccination

Abstract

LIVE measles vaccine¹ given without gamma globulin protects children from the clinical manifestations of natural measles even if given as late as three days after exposure.^{2 3 4} Krugman et al.⁵ have suggested that this early protective effect may be an example of viral interference in man. This inhibition of viral replication due to a prior viral infection may be mediated by interferon, an antiviral protein made by animal cells in response to a viral infection. Interferon has been found in the pharyngeal washings of patients with influenza,⁶ in the spinal fluid of certain patients with viral meningitis⁷ and occasionally in the . . .