Which term corresponds to the description 'Lower airway infection in infants'?

• A. RSV
• B. Bronchiolitis
• C. Epiglottitis
• D. Croup

Answer: (B)

Bronchiolitis is a lower airway infection in infants, involving inflammation of the bronchioles—the tiny airways in the lungs. It most often follows a viral illness and is classically caused by RSV, which is the common culprit behind bronchiolitis in young infants. This condition presents with symptoms like rapid breathing, chest retractions, and wheezing as the virus inflames and narrows the small airways.

In contrast, epiglottitis and croup involve the upper airway (epiglottis and larynx/trachea, respectively) and typically produce symptoms such as drooling and high fever with urgent airway symptoms (epiglottitis) or a barking cough and inspiratory stridor (croup). RSV is a virus that can cause bronchiolitis, but it’s not the disease name itself.