What is the recommended schedule for vaccinating a child? What about adults?

For children, the first dose should be given at age 12 months with a second dose given at age 4 through 6 years. The second dose could be given earlier, if necessary, as long as there is a 3-month (12-week) interval between doses. Although a 3-month minimum interval is recommended in children younger than age 13, the second dose does not need to be repeated if separated from the first dose by a shorter interval of at least 4 weeks.

All children age 13 years and older as well as adults without evidence of immunity should also have documentation of 2 doses of varicella vaccine, separated by a minimum interval of 4 weeks.