INTRANASALLY ADMINISTERED RUBELLA VACCINE

The RA27/3 strain of rubella virus, which is an effective attenuated strain when given subcutaneously, is also immunogenic when given intranasally. Given in a dose of 1000 plaque-forming units (P.F.U.) in the form of nose drops, the virus produced antibodies in 93% of subjects (mainly children); a dose of 100 P.F.U. immunised 50% of subjects. Clinical reaction was absent except for occasional lymphadenopathy. Nasopharyngeal virus excretion was sporadic, and there was no spread to contacts. Antibody responses to intranasal vaccination were equivalent to those obtained after subcutaneous inoculation.