Virology USMLE Step 1 Practice Question
A 4-year-old boy with acute onset of fever, cough, and inspiratory stridor is brought to the emergency department. He has not been vaccinated. Laryngoscopy reveals subglottic narrowing with a characteristic 'pencil point' sign on neck X-ray. Lateral neck radiograph shows subglottic edema. Which of the following viruses is most likely responsible for this presentation?
Answer choices
- AParainfluenza virus type 1Correct answer
- BInfluenza A virus
- CEpstein-Barr virus
- DRespiratory syncytial virus
- EHuman metapneumovirus
- FAdenovirus
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