Pertussis is an epidemic disease caused by Bordetella pertussis and also to a lesser extent by Bordetella parapertussis. Classical illness lasts 4–8 weeks and is characterized by paroxysms of coughing with posttussive vomiting and whooping; however, 47.4% of primary infections last 4 weeks or less. Whole cell pertussis vaccines are generally highly efficacious. All whole cell vaccines are reactogenic, causing fever and local reactions in many vaccinees. In the past, these vaccines were thought to cause infant deaths and brain damage. However, several large epidemiologic studies indicate that whole cell vaccines do not cause infant deaths or neurologic disease. Recent studies indicate that neither immunization nor infection give long-term immunity. As a result, B. pertussis infections are endemic in adult populations. The future control of B. pertussis will require immunization schedules with new acellular vaccines that include booster doses in older children and adults.