An acute infection of the tracheobronchial tree caused by Bordetella pertussis, a bacteria species exclusive to infected humans. The disease (also known as pertussis) follows a prolonged course beginning with a runny nose, and finally develops into violent coughing, followed by a slow period of recovery. The coughing stage can last 2–4 weeks, with a whooping sound created by an exhausted individual rapidly breathing in through a narrowed glottis after a series of wrenching coughs. The classical disease occurs in children 1–5 years of age, but in immunized populations infants are at greatest risk and adults with attenuated (and unrecognized) disease constitute a major source of transmission to others. Bordetella pertussis is highly infectious, particularly following face-to-face contact with an individual who is coughing. The disease is caused by structural components and extracellular toxins elaborated by B. pertussis. Multiple virulence factors produced by the organism play important roles at various stages of pertussis.

A vaccine produced from whole B. pertussis cells and combined with diphtheria and tetanus toxoids has been used throughout the world for routine childhood immunization. Concern over vaccine morbidity has caused immunization rates to decline in some developed countries. These drops in immunization rates have often been followed by widespread outbreaks of disease, including deaths. Considerable effort has been directed toward the development of a vaccine which would minimize side effects but maintain efficacy. A new acellular vaccine is available and has fewer side effects than the whole-cell vaccine. Diphtheria Tetanus

Although B. pertussis is susceptible to many antibiotics, their use has little effect once the disease reaches the coughing stage. Erythromycin is effective in preventing spread to close contacts and in the early stage.