Clinical and Laboratory Studies of Live Attenuated RA 27/3 and HPV 77-DE Rubella Virus Vaccines

Abstract Comparative studies of RA 27/3 and HPV 77-DE rubella virus vaccines were carried out in children and adults. RA 27/3 vaccine induced antibody in a larger proportion of individuals and at a substantially higher titer level than did HPV 77-DE vaccine. Additionally, the RA 27/3 vaccine induced theta and iota antibodies that are commonly found after infection with rubella virus in nature. The greater serologic responses to RA 27/3 virus were achieved without any important increase in clinical reactions and there was no evidence for contagious spread of the infection. There was slightly greater occurrence of rash and lymphadenopathy after RA 27/3 vaccine compared with HPV 77-DE but the rate for occurrence of arthritis was substantially lower. Nearly 8000 initially seronegative persons received the RA 27/3 vaccine in the present studies. The seroconversion rate was 98% and there were no clinical reactions of importance. Follow-up studies showed undiminished retention of antibody titer for at least 2 years following vaccination with RA 27/3 vaccine.