Simultaneous administration of varicella vaccine and other recommended childhood vaccines--United States, 1995-1999.

Live attenuated varicella vaccine (Var) is recommended in the United States for children aged 12-18 months and for susceptible older children, adolescents, and adults. The Advisory Committee on Immunization Practices recommends that Var be administered either simultaneously with measles-mumps-rubella (MMR) vaccine or separately by > or =30 days. This report summarizes an evaluation of these recommendations, which found that a decrease in Var effectiveness occurred when Var was administered <30 days after MMR; therefore, as currently recommended, physicians should administer Var simultaneously with MMR or wait at least 30 days if the vaccines are administered separately.