Evaluation of a live attenuated varicella vaccine in 15- to 18-month-old healthy children.

A clinical trial was conducted in Taiwan in 15- to 18- month-old healthy children to study the reactogenicity and immunogenicity of live varicella vaccine combined with standard measles-mumps-rubella vaccine. A total of 118 varicella antibody-negative children were enrolled. They received one dose of varicella vaccine and one dose of measles-mumps-rubella vaccine at the same time. The vaccines were well tolerated; adverse reactions were mild and infrequent, with 2% of vaccines developed skin rash. No vesicular rash was seen. Concomitant varicella vaccination did not significantly increase the incidences of reactions associated with MMR vaccine. The seroconversion rates to varicella, measles, mumps and rubella all approached 100%. This study confirmed that simultaneous administration of live attenuated varicella vaccine and MMR vaccine was safe and immunogenic in healthy young children in Taiwan.