Some children in my practice are not up to date on their immunizations, and pertussis is circulating in our community. Can you guide me in determining how to make the decision about which vaccine to choose?

You should use DTaP in children younger than age 7 years. In addition, ACIP recommends giving a dose of Tdap to children age 7–10 years who did not finish a minimum 3-dose series of pertussis-containing vaccines before their 7th birthday or for whom their pertussis vaccine status is unknown. Children age 7–10 who require more than one dose of tetanus-containing vaccine to be up to date may be given either Td or Tdap for doses needed after the initial Tdap dose. Although this is an off-label use of the vaccines, it’s important that you vaccinate these vulnerable children with Tdap as well as any other adolescent or adult who hasn’t received Tdap previously.