Two Doses of Measles Mumps Rubella (MMR) Vaccine

A schedule of two doses of measles mumps rubella vaccine (MMR) at an interval of six weeks was tried in children aged between 12 and 48 months. One hundred percent seroconversion was attained in the measles HI (hemagglutinin inhibition) test, rubella HI test, and mumps ELISA test in both groups of children who received NIH (National Institute of Health, Japan) MMR lot B-30 and Kitasato MMR lot TV-1. The possibility of vaccine failure with one dose of measles vaccine is not negligible 1], and the frequency of vaccine failure increases if three vaccines are combined in the form of MMR. Our observations revealed that a few of the children who had received one dose of MMR remained seronegative with regard to measles HI antibody and rubella HI antibody, and that some of the children remained seronegative with regard to mumps ELISA antibody. A schedule of two doses of MMR was shown to be helpful in reinforcing immunity in children who did not respond satisfactorily to one dose of MMR. We concluded that two doses of MMR are preferable to control measles, mumps and rubella infections.