The Pertussis Epidemic in Oklahoma

The report by Nkowane and associates1in this issue ofAJDCon epidemic pertussis in Oklahoma in 1983 contains many important observations and is particularly important in 1986 because of the many pertussis vaccine—related events that have occurred during the last four years in the United States. The epidemic in Oklahoma in 1983 occurred at a time of relatively high vaccine utilization. The epidemic was due to underutilization and delayed utilization of the vaccine in selected young children who were not exposed to enforcement policies of existing immunization laws, and was also due to the cyclic nature of pertussis.2This increased incidence of pertussis in Oklahoma in 1983 cannot be attributed to decreased vaccine utilization due to adverse publicity about pertussis immunization, nor can it be attributed to vaccine failure. The findings in the Oklahoma study1are particularly useful in that they point