Adenovirus and croup in children

Croup is a clinical pattern rather than the name of one specific virus. Adenovirus is one possible cause. It can also cause fever, runny nose, sore throat or red eyes, so a child may have symptoms beyond the characteristic seal-like cough.

Viral inflammation narrows the airway around the voice box and windpipe. Air moving through that narrowed area creates stridor, a harsh high-pitched sound heard mainly when breathing in. Stridor differs from wheeze, which is usually a musical sound from the chest and is often more noticeable when breathing out.

Croup commonly presents with a barking cough and hoarseness. Symptoms can sound worse when a child is crying or distressed because breathing becomes faster and more forceful. The sound alone does not identify which virus is responsible, and viral testing is not needed for every uncomplicated episode.

Keep the child upright in a comfortable position, speak calmly and offer frequent drinks if swallowing is easy. Distress can intensify noisy breathing, so avoid unnecessary throat examination or forcing the child to lie down. Use fever or discomfort medicine only in a child-appropriate form and dose recommended by a clinician or pharmacist.

Do not expose the child to hot steam because it can burn and has no reliable role in opening the airway. A clinician may use a steroid medicine to reduce swelling; more significant symptoms may require inhaled medicine and observation in a healthcare setting. Antibiotics do not treat viral croup.

Call emergency services if stridor is present while the child is calm, breathing is laboured, the skin pulls in around the ribs or neck, lips look blue or grey, the child is unusually sleepy or agitated, or breathing becomes quiet despite visible effort. Drooling, inability to swallow, or sitting forward and refusing to lie down also requires emergency assessment.

Seek prompt clinical advice when the barking cough is worsening, fever accompanies a child who looks very unwell, fluid intake or urine output falls, or you are uncertain whether the noise is stridor. A young infant or a child with an airway condition deserves a lower threshold for assessment.

Tell the clinician whether noisy breathing happens only during crying or also at rest, how easily the child drinks, and whether drooling, chest pulling, unusual sleepiness or colour change occurred. Ask how any prescribed medicine should be given and which returning symptoms mean the child needs reassessment.