Diphtheria (D) vaccines contain toxoids prepared from Corynebacterium diphtheriae. Tetanus (T) vaccines contain toxoids prepared from Clostridium tetani. Acellular (a) pertussis (P) vaccines contain semipurified or purified components of Bordetella pertussis. Whole-cell pertussis vaccine is no longer available in the US because of concerns about adverse effects, but it is still available in other parts of the world. There are 2 preparations of the acellular vaccine:

Tdap contains lower doses of diphtheria and pertussis components (indicated by the lower case d and p).

DTaP is a routine childhood vaccination (see Table: Recommended Immunization Schedule for Ages 0–6 yr).

Tdap is routinely given as a single lifetime dose to children at age 11 or 12 yr and to people ≥ 13 yr who have never received Tdap (regardless of the interval since the last tetanus-diphtheria [Td] vaccine—see Tetanus-Diphtheria Vaccine) or whose vaccine status is unknown.

Additional boosters of Tdap are also recommended for

Adults who require a tetanus toxoid-containing vaccine as part of wound management and who have not previously received Tdap are given Tdap instead of Td.

People who have had pertussis should still receive a pertussis-containing vaccine as per routine recommendations.

Contraindications for DTaP and Tdap are

Because tetanus vaccination is important, people who have had an anaphylactic reaction to components in DTaP or Tdap should be referred to an allergist to determine whether they are allergic to tetanus toxoid. If not, they can be vaccinated with tetanus toxoid (TT) vaccine. Adults with a history of encephalopathy can be vaccinated with Td, and children can be given diphtheria-tetanus (DT) instead of Tdap.

Precautions vary depending on the formulation.

For DTaP and Tdap, they include

For DTaP only, precautions include

For Tdap only, precautions include

The dose for DTaP or Tdap is 0.5 mL IM.

The DTaP vaccine is given as 5 primary and 1 booster IM injections during childhood as follows: at age 2 mo, 4 mo, 6 mo, 15 to 18 mo, and 4 to 6 yr (before school entry). The 5th dose is not necessary if the 4th dose was given at age ≥ 4 yr.

A single booster of Tdap is given, except for pregnant women, who should have a dose during each pregnancy.

Adverse effects are rare and are mostly attributable to the pertussis component. They include encephalopathy within 7 days; a seizure, with or without fever, within 3 days; ≥ 3 h of persistent, severe, inconsolable screaming or crying within 48 h; collapse or shock within 48 h; temperature of ≥ 40.5° C, unexplained by another cause, within 48 h; and immediate severe or anaphylactic reaction to the vaccine.

If the pertussis vaccine is contraindicated, a combined diphtheria and tetanus vaccine is available without the pertussis component (see Tetanus-Diphtheria Vaccine).

Mild adverse effects include redness, swelling, and soreness at the injection site.