Acute bronchiolitis causes: what parents should know

Several respiratory viruses can produce the same pattern. The infection spreads in droplets and respiratory secretions, especially through close contact, coughs, sneezes, contaminated hands, and frequently touched objects.

After entering the nose or throat, the virus can move into the bronchioles. Swelling, mucus, and shed cells narrow these tiny passages, so air movement may become noisy or effortful.

Bronchiolitis commonly presents with a runny nose followed by cough, faster breathing, feeding difficulty, or wheezing. A fever may occur, but its presence or absence does not by itself show how serious the breathing problem is. Young infants and children born early can have less reserve when breathing or feeding becomes difficult.

Wash hands before touching the child or preparing feeds, clean shared surfaces, avoid smoke exposure, and limit close contact with people who have respiratory symptoms. Do not share cups, utensils, or towels during the illness.

Offer smaller feeds more often if congestion makes feeding tiring. Saline nose drops and gentle suction before feeds may help an infant breathe through the nose. Antibiotics do not treat the viruses that cause bronchiolitis; a clinician should decide whether any medicine or breathing treatment is appropriate.

Seek urgent medical care if the child has pauses in breathing, blue or grey lips, severe chest pulling, grunting, marked drowsiness, or is struggling to breathe. These signs require assessment based on the child's condition, not on which virus may be responsible.

Arrange prompt assessment for worsening breathing, much less drinking, repeated vomiting, noticeably fewer wet nappies, unusual sleepiness, or a fever in a very young infant. Call emergency services if the child is unresponsive or cannot breathe adequately.

Ask how to judge breathing effort, which hydration signs to track, and whether the child's age, birth history, heart condition, lung condition, or immune problem changes the care plan. Also confirm which medicines to avoid and when the child should be reviewed again.