Pertussis (whooping cough) is a respiratory tract infection characterized by a paroxysmal cough. The most common causative organism is Bordetella pertussis (see the image below), though Bordetella parapertussis has also been associated with this condition in humans. Pertussis remains a significant cause of morbidity and mortality in infants younger than 2 years.

Signs and symptoms

Pertussis is a 6-week disease divided into catarrhal, paroxysmal, and convalescent stages, each lasting 1-2 weeks.

Stage 1 – Catarrhal phase

• Nasal congestion
• Rhinorrhea
• Sneezing
• Low-grade fever
• Tearing
• Conjunctival suffusion

Stage 2 – Paroxysmal phase

• Paroxysms of intense coughing lasting up to several minutes, occasionally followed by a loud whoop
  • Chronic cough, which may last for weeksPosttussive vomiting and turning red with coughing

• Diagnosis

  The diagnosis of pertussis is made by isolation of B pertussis in culture. A polymerase chain reaction (PCR) test can also be performed.

  • The culture specimen should be obtained during the first 2 weeks of cough by using deep nasopharyngeal aspiration
  • For PCR testing, nasopharyngeal specimens should be taken at 0-3 weeks following cough onset
  • The CDC recommends a combination of culture and PCR assay if a patient has a cough lasting longer than 3 weeks
  • Early serial monitoring of white blood cell (WBC) counts is warranted

  Management

  Goals of treatment

  • Limit the number of paroxysms
  • Observe the severity of cough and provide assistance when necessary
  • Maximize nutrition, rest, and recovery

  Pharmacologic therapy

  • Antimicrobial agents and antibiotics can hasten the eradication of B pertussisand help prevent spread
  • Erythromycin, clarithromycin, and azithromycin are the preferred agents for patients aged 1 month or older