Immune response to simultaneous administration of a combined measles,mumps and rubella vaccine with booster doses of diphtheria-tetanus and poliovirus vaccine

A combined vaccine against measles (Edmonston-Zagreb 19 strain), mumps (Rubini strain) and rubella (Wistar RA 27/3 strain) was administered to a group of 46 children aged 10–12 months simultaneously with booster doses of compulsory diphtheria-tetanus toxoid and oral poliovirus vaccine. A second group of 53 children aged 15–24 months who had received booster doses of the compulsory vaccines 5 to 12 months before was also vaccinated.The same seroconversion rates (100%) and similar antibody titers for rubella were observed in both groups. The same seroconversion rates for mumps (93%) and similar rates for measles (98 and 94%) were observed in the two groups.Significantly lower antibody titers for measles and mumps were found in the first group, but they were compensated by an earlier protection, a reduction of number of visits for immunization, costs for the community, and improvement in parental compliance.These results confirm that Edmonston-Zagreb 19 and Rubini strains are still immunogenic even when they are combined with Wistar RA 27/3 strain. Moreover, a long term follow-up in order to verify the persistence of protective antibody levels in both groups of children, could suggest that combined measles, mumps and rubella vaccine could be given earlier (at 10–12 months of age), simultaneously with booster doses of diphtheria and tetanus toxoid and of trivalent oral poliovirus vaccine.