Children should receive the U.S. FDA recommended COVID-19 vaccine dosage for their age group, even if they change age groups between doses. If a person moves from a younger age group to an older age group during the primary series or between the primary series and the booster dose, they should receive the vaccine product and dosage for the older age group for all subsequent doses. Children who started a Pfizer 3-dose series should receive a total of 3 doses of age-appropriate Pfizer vaccine to complete their vaccination, even if they turn 5 before receiving all doses.
For example, children who started a Pfizer 3-dose series at age 4 and turned 5 after the first dose should receive a second and third dose of the Pfizer vaccine for ages 5 to 11 to complete their vaccination series. The second dose should be given 3 to 8 weeks after the first dose, and the third dose should be given at least 8 weeks after the second dose.
Children who started a Pfizer 3-dose series at age 4 and turned 5 after the second dose should receive a third dose of the Pfizer vaccine for ages 5 to 11 to complete their vaccination series. The third dose should be given at least 8 weeks after the second dose.
Please consult with your child’s primary care provider for more information. See this graphic for additional information about Pfizer vaccination for children who transition from a younger to older age group.