Clinical Question: Does the use of a diphtheria and tetanus toxoids and acellular pertussis vaccine (DTaP) produce pertussis antibodies in adolescents and adults?

Setting: Outpatient (specialty)

Study Design: Randomized controlled trial (double-blinded)

Allocation: Concealed

Synopsis: Waning immunity in adolescents and adults may explain the significant increase in the incidence of pertussis. No booster pertussis vaccine is currently available for adolescents or adults. The investigators randomly assigned in double-blind fashion 4,480 healthy adolescents and adults, 11 to 64 years of age, to receive a single 0.5-mL intramuscular dose of tetanus and diphtheria toxoids vaccine (Td) or DTaP. Participants were observed immediately following the vaccine for 30 minutes, and adverse events were recorded for six months. Follow-up occurred for 97 percent of the patients. Persons blinded to treatment group assignment assessed outcomes.

Using modified intention-to-treat analysis (all patients receiving study vaccine), more than 94 percent of the DTaP group and nearly 100 percent of the Td group developed protective antibody concentrations for diphtheria and tetanus. Antibody titers to pertussis in persons receiving DTaP exceeded levels found in infants following routine immunization at two, four, and six months with children’s DTaP. The incidence of adverse events at vaccination and follow-up was similar between the DTaP and Td groups.

Bottom Line: Use of DTaP results in antibody levels to tetanus, diphtheria, and pertussis in adolescents and adults. It is likely that recommendations soon will be made for its use in these groups. The study did not evaluate the effect on the incidence of pertussis in these age groups. Further studies on long-term patient-oriented outcomes will be important. (Level of Evidence: 1b)