Home / Ask The Experts / If a child has already received 5 doses of DTaP by their fourth birthday (with the appropriate 6-month intervals between #3 and #4 and also between #4 and #5), is a booster dose after the fourth birthday necessary?

Diphtheria
Scheduling Vaccines
Pertussis
Scheduling Vaccines
Tetanus
Scheduling Vaccines

If a child has already received 5 doses of DTaP by their fourth birthday (with the appropriate 6-month intervals between #3 and #4 and also between #4 and #5), is a booster dose after the fourth birthday necessary?

In general, a child should receive no more than four doses of DTaP before 4 years of age (preferably by 2 years of age). The ACIP recommends that a dose of DTaP be given at 4–6 years of age. Many states have school immunization laws which also require at least one dose of DTP/DTaP on or after the fourth birthday. This dose is important to boost immunity to pertussis.

Last reviewed: March 31, 2022

All Ask the Experts Questions

This page was updated on April 24, 2022.