A CDC study has shown a small increased risk for febrile seizures during the 24 hours after a child receives the inactivated influenza vaccine at the same time as the PCV13 vaccine or DTaP vaccine. However, the risk of febrile seizure with any combination of these vaccines is small and ACIP recommends giving these vaccines at the same visit if indicated. The risk for febrile seizures in children who received PCV15 or PCV20 concurrently with an influenza vaccine has not been studied. See www.cdc.gov/vaccinesafety/concerns/febrile-seizures.html for more information about febrile seizures after vaccination.
Ask the Experts: Tetanus: Scheduling Vaccines
Children, age 7 years and older, and adults who have never received tetanus-containing vaccines, or whose vaccination history is unknown, should receive the 3-dose series. In this situation, ACIP recommends Tdap for dose #1, followed 4 weeks later by Td or Tdap for dose #2, followed at least 6 months later by Td or Tdap for dose #3. The amount of protection provided by one or more doses of Tdap in a person who has not previously received pertussis vaccine is not known. Following the primary series, booster doses of Td or Tdap should be given every 10 years thereafter.
The fourth dose of DTaP may be given as early as age 12 months if at least 6 months have passed since the third dose.
You should try to achieve at least 4 total doses. Give additional doses of DTaP with 4-week intervals until you achieve 3 total doses. Then, if 6 months pass and the child has not turned seven years old, give the 4th dose of DTaP: if the child has turned seven years old, you may administer a dose of Tdap vaccine at that time.
Although the child would be considered complete for tetanus and diphtheria toxoids, she is not complete for pertussis vaccine. DTaP vaccines are FDA-approved only through age 6 years so no more DTaP doses are recommended.
However, ACIP recommends that children age 7–10 years who are not fully vaccinated against pertussis (defined as 5 doses of DTaP or 4 doses of DTaP if the fourth dose was administered on or after the fourth birthday) and who do not have a contraindication to pertussis vaccine should receive a single dose of Tdap to provide protection against pertussis. If the child in this case is age 7–9 years at the time of Tdap vaccination, the next dose due will be the routine adolescent dose of Tdap at age 11 or 12 years. If the child is age 10, the dose counts as the adolescent dose and no additional dose at age 11 or 12 years is recommended.
If DTaP #4 is given with at least a 4-month interval after DTaP #3, it does not need to be repeated. The minimum age of 12 months for the fourth dose must be met. Decreasing the interval to less than 6 months, however, is not recommended.
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.
ACIP and AAP both recommend that children receive no more than 6 doses of diphtheria and tetanus toxoids (e.g., DT, DTaP, DTP) before the seventh birthday because of concern about adverse reactions, primarily local reactions. Half doses of DTaP are also not recommended under any circumstances, and should not be counted as part of the vaccination series. Only documented doses (i.e., those recorded in an electronic or written record) count toward the maximum of 6 doses.
The minimum interval between DTaP #4 and DTaP #5 is six months. Remember that the minimum age for DTaP #5 is age 4 years.
If DTaP is not contraindicated and the child has not received all of the age-appropriate doses of pertussis-containing vaccine, it would be best to try to administer as many doses of DTaP as possible before the child reaches his 7th birthday in order to confer protection against pertussis. Give additional doses of DTaP with 4-week intervals until you achieve 3 total doses. Then, give additional doses with 6-month intervals, not to exceed 6 total doses of diphtheria- and tetanus-containing vaccine by the child’s 7th birthday.