Neurologic events following diphtheria-tetanus-pertussis immunization

The frequency of serious neurologic events following the administration of 106,000 doses of diphtheria-tetanus-pertussis vaccine at Group Health Cooperative of Puget Sound was determined using a population-based case-control study with disease ascertainment through pharmacy and hospitalization records. There were no cases of acute unexplained encephalopathies in close temporal relation to vaccination. There was the new onset of one serious seizure disorder in the three days following immunization, with 1.13 expected on the basis of chance alone.