A 15-month-old boy is brought to the physician by her parents for a 2-day history of progressive hoarseness and dry cough. Her temperature is 101 F (38.3 C) and respiratory rate 22/minute. Pulse oximetry is 96% on room air. Physical exam shows mild oropharyngeal erythema without exudates or lymphadenopathy. A harsh, barking cough is heard. Which of the following is the most likely explanation for this patient’s findings?
DNA virus; enveloped
DNA virus; non-enveloped
Gram-negative coccus
Gram-negative rod
Gram-positive coccus
Gram-positive rod
RNA virus; enveloped
RNA virus; non-enveloped
