There are two basic products that can be used in children younger than age 7 years (DTaP and DT) and two that can be used in older children and adults (Td and Tdap). Some people get confused between DTaP and Tdap and others get confused between DT and Td. Here’s a hint to help you remember. The pediatric formulations usually have 3–5 times as much of the diphtheria component than what is in the adult formulation. This is indicated by an upper-case “D” for the pediatric formulation (i.e., DTaP, DT) and a lower case “d” for the adult formulation (Tdap, Td). The amount of tetanus toxoid in each of the products is equivalent, so it remains an upper-case “T.”
Ask the Experts: Diphtheria: Vaccine Products
There are two different DTaP products currently used in the U.S. for the primary series for children ages 2 months through 6 years (Daptacel [Sanofi] and Infanrix [GSK]). ACIP has recommended that, whenever feasible, healthcare providers should use the same brand of DTaP vaccine for all doses in the vaccination series. If vaccination providers do not know or have available the type of DTaP vaccine previously administered to a child, any DTaP vaccine may be used to continue or complete the series. For vaccines in general, vaccination should not be deferred because the brand used for previous doses is not available or is unknown (see the ACIP’s General Best Practices Guidance for Immunization at www.cdc.gov/vaccines/hcp/acip-recs/general-recs/timing.html).
If the DTaP brand used for previous doses is not known or not in stock, use whatever DTaP vaccine you have available for all subsequent doses.
If Tdap was inadvertently administered to a child under age 7 years, it should not be counted as either the first, second, or third dose of DTaP. The dose should be repeated with DTaP. Continue vaccinating on schedule. If the dose of Tdap was administered for the fourth or fifth DTaP dose, the Tdap dose can be counted as valid. Please remind your staff to always check the vaccine vial at least 3 times before administering any vaccine.
Yes. In this situation, a second dose of Tdap should be administered at the recommended age of 11 or 12 years.
Yes. The updated ACIP recommendations for the use of Tdap vaccine state that Tdap or Td may be used in any situation where Td only was previously recommended. The updated guidelines are available at www.cdc.gov/mmwr/volumes/69/wr/pdfs/mm6903a5-H.pdf.
ACIP recommends that patients needing prophylaxis against tetanus always be given either Td or Tdap rather than TT, as long as there is no contraindication to the other vaccine components. If it’s already been given and the person had not yet received Tdap as an adolescent or adult, you should make certain that he gets Tdap as soon as feasible. If he had received Tdap previously, he can wait until the next scheduled booster dose is due to get his routine Td or Tdap booster.
The first step is to inform the parent/patient that you administered the wrong vaccine. Next, follow these guidelines:
- Tdap given to a child younger than age 7 years as either dose 1, 2, or 3, is not valid. Repeat with DTaP as soon as feasible.
- Tdap given to a child younger than age 7 years as either dose 4 or 5 can be counted as valid for DTaP dose 4 or 5.
- Tdap or DTaP given to a fully vaccinated child age 7–9 years: the child should receive the routine adolescent Tdap dose at age 11–12 years.
- Tdap or DTaP given to a fully vaccinated child age 10 years: count this dose as the routine adolescent Tdap dose recommended at age 11–12 years.
- DTaP given to an undervaccinated child age 7–9 years: count this dose as a Tdap dose of the catch-up series. The child should receive the routine adolescent booster dose of Tdap at age 11–12 years.
- DTaP given to an undervaccinated child age 10 years: count this dose as the routine adolescent Tdap dose recommended at age 11–12 years.
- DTaP given to a person age 11 years or older: count this dose as a routine Tdap dose.
Note that DTaP is neither approved nor recommended for people older than 6 years (except hematopoietic stem cell transplant recipients in some situations; see www.cdc.gov/vaccines/hcp/acip-recs/general-recs/immunocompetence.html).
Yes. The DTaP in the Pentacel can be counted. Although Pentacel is licensed as a 4-dose series and this may represent a fifth dose of Pentacel (in which case it would be off-label use), the dose of DTaP counts as the fifth dose of DTaP.
The same principle applies to Vaxelis (DTaP-IPV-Hib-HepB, MCM), which is licensed for use in children ages 6 weeks through 4 years as a 3-dose series of vaccinations routinely recommended at age 2 months, 4 months, and 6 months. The DTaP in a dose of Vaxelis inadvertently administered after the 5th birthday or as the 4th or 5th dose of DTaP (off-label use) may be counted as valid and does not need to be repeated.