Table 4.

DTaP and DTP Vaccine Efficacy Against Cough Illness of ≥7 Days Duration as a Result of Bordetella pertussis Infection Using the Principal Efficacy Analysis Case Definitions* and the Exclusion of Noncases Who Received Macrolide Antibiotics or Trimethoprim-Sulfamethoxazole During the Exposure Period

VaccineNo. Cases/
No. Exposed
(Attack Rate)
%
Vaccine
Efficacy
95%
Confidence
Interval
7 to 28 Day Postexposure Observation Period
 DT11 /23 (48%)
 DTP6 /52 (12%)7643–90
 DTaP12 /45 (27%)44−6–71
7 to 42 Day Postexposure Observation Period
 DT16 /22 (73%)
 DTP6 /52 (12%)8465–93
 DTaP13 /43 (30%)5830–75
  • Abbreviations: DTaP, diphtheria-tetanus toxoids, acellular pertussis vaccine, adsorbed; DTP, diphtheria-tetanus toxoids, whole cell pertussis vaccine, adsorbed; DT, diphtheria-tetanus toxoids vaccine.

  • * See Table 1.