Last updated on: February 10th, 2021

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Clinicals - History

Known exposure to pertussis

Pertussis, or whooping cough, is caused by the bacteria Bordetella pertussis. It is easily transmitted from person to person via airborne droplets. Contact with a known case of pertussis should raise suspicion for the disease in any symptomatic patient.

Stage 1: Catarrhal

Generally occurs 5 to 10 days after exposure and lasts 7 to 10 days. At this time there is coryza, low-grade fever, and a mild cough that gradually worsens.

Stage 2: Paroxysmal

This phase generally lasts 1 to 6 weeks. The classic triad of symptoms is paroxysms of cough, whooping on inspiration, and post-tussive vomiting. The paroxysms may be worse in older infants and young children, and are generally milder in adolescents and adults, especially if immunized. They are often absent in young infants.

This occurs due to the inability to expel mucus from tracheobronchial tree.

Stage 3: Convalescent

This phase lasts 2 to 6 weeks or longer. There is a gradual resolution of the paroxysmal cough. However, paroxysms may return with respiratory infections for several months.

Prolonged cough without paroxysms

The classic triad may be absent, especially in adolescents, adults, and immunized children.


Infants may be without the classic symptoms and exhibit only apnea.

Neurologic complications

Seizures and encephalopathy may occur in infants. Encephalopathy is thought to be either due to lack of oxygenation or a direct effect of bacterial toxins.

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