The safety of acellular pertussis vaccine vs whole-cell pertussis vaccine. A postmarketing assessment.
OBJECTIVE
To determine the impact of the introduction of acellular pertussis vaccine for the fourth and fifth doses of the diphtheria and tetanus toxoids and pertussis vaccine series in children on rates of reported vaccine-associated adverse events in the United States.


METHODS
Analysis of postmarketing vaccine adverse event data from the Vaccine Adverse Event Reporting System during the years 1991 to 1993.


METHODS
Approximately 27 million doses of diphtheria and tetanus toxoids and pertussis vaccine and 5 million doses of diphtheria and tetanus toxoids and acellular pertussis vaccine were distributed from 1991 to 1993 to children 15 months to 7 years of age.


METHODS
Rates of reported fever, seizures, and hospitalizations after pertussis vaccination.


RESULTS
Rates of reported adverse events per 100,000 vaccinations were significantly lower after administration of diphtheria and tetanus toxoids and acellular pertussis vaccine than diphtheria and tetanus toxoids and pertussis vaccine for the following outcomes: all reports, 2.9 vs 9.8; fever, 1.9 vs 7.5; seizures, 0.5 vs 1.7; and hospitalizations, 0.2 vs 0.9.


CONCLUSIONS
These results confirm that minor adverse events are less frequent after administration of the acellular pertussis vaccine. In addition, these data suggested that seizures and hospitalizations associated with pertussis vaccination are less frequent after administration of the acellular pertussis vaccine in age groups for which it is now recommended.
Rosenthal
S
S
National Immunization Program, Centers for Disease Control and Prevention, Atlanta, GA, USA.
Chen
R
R
Hadler
S
S
D002648:Child; D002675:Child, Preschool; D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000009:adverse effects; D005260:Female; D005334:Fever / Q000139:chemically induced; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D008297:Male; D010567:Pertussis Vaccine / Q000009:adverse effects*; D011358:Product Surveillance, Postmarketing; D012640:Seizures / Q000139:chemically induced; D014481:United States; D017778:Vaccines, Combined / Q000009:adverse effects
D015721:Diphtheria-Tetanus-Pertussis Vaccine; D010567:Pertussis Vaccine; D017778:Vaccines, Combined