Pertussis / Whooping Cough

Pertussis is caused by the gram-negative aerobic bacterium Bordetella pertussis. It attaches to the ciliated epithelial cells of the respiratory tract and releases toxins. These toxins impair normal mucociliary clearance, increase airway irritation, and trigger prolonged coughing paroxysms. The cough may persist for weeks to months because airway inflammation and impaired clearance continue even after bacterial burden decreases. This is why antibiotics help most with transmission reduction and are most effective for symptom severity when started early. For REx-PN (Canada), items rarely announce the topic in the first sentence. Anchor to objective data, trajectory, and the safest next step for the role named in the stem before distractors compete. On the exam, writers often pair stable-sounding options with unstable data—notice the mismatch before you commit. If the stem names a license or role, reread that line; scope errors are classic trap answers even when the clinical topic is familiar. Run a 60-second scan: breathing work and oxygenation, perfusion and end organs, neuro baseline, likely infection sources, and devices that can fail quietly. When two answers feel partly right, pick the...