Safety and immunogenicity of a combined live attenuated measles, mumps, rubella, and varicella vaccine (MMR(II)V) in healthy children.

An investigational tetravalent combined measles, mumps, rubella, and varicella vaccine and measles-mumps-rubella and varicella vaccines at separate injection sites given at the same visit were evaluated with respect to safety and cell-mediated and humoral immune responses at 6 weeks and 1 year after vaccination. Varicella seroconversion rates and lymphocyte proliferation responses were 100% for both vaccine groups at 6 weeks and 1 year. However, the antibody titer to varicella was lower in the combined vaccine group at 6 weeks, but there was no statistical difference in cell-mediated immune responses. One-year geometric mean titers were not statistically different. Seroconversion rates for measles, mumps, and rubella were 100% for both vaccine at 6 weeks and 1 year. Long-term follow-up of these immune responses is planned.