It begins with a runny nose and a mild cough, but after a few days your baby is breathing faster, coughing more and struggling to feed. Bronchiolitis is a common chest infection in babies under 1, usually caused by RSV, and it peaks in winter. Most cases are mild, but knowing the signs of bronchiolitis in babies that need help is important.
Quick answer: bronchiolitis in babies
- What it is: a viral infection that causes swelling in the small airways of the lungs.
- Most common in babies under 12 months, especially under 6 months.
- Symptoms are often worst on days 3 to 5, and the cough can last 2 to 4 weeks.
- Get help for fast or difficult breathing, pauses in breathing or taking less than half usual feeds.
Symptoms
- runny or blocked nose and mild fever at first
- a persistent, dry cough
- fast or noisy breathing, sometimes wheezing
- feeding less and fewer wet nappies
- irritability or tiredness
Warning signs: get help straight away
- breathing that looks hard work, with ribs or the tummy sucking in
- grunting or flaring nostrils
- pauses in breathing, or blue or grey lips or tongue: call emergency services
- taking less than half of usual feeds, or no wet nappy for 12 hours
- very sleepy, floppy or hard to wake
Caring for your baby at home
- Offer smaller, more frequent feeds.
- Use saline drops and gentle suction to clear the nose before feeds.
- Give paracetamol (acetaminophen) for fever or discomfort if needed, at the right dose.
- Keep your baby upright while awake; always lay them on their back to sleep.
- Keep the home smoke-free.
Antibiotics and cough medicines do not help bronchiolitis. See RSV in babies and caring for a sick baby at night.
Who is at higher risk?
- babies under 3 months
- babies born prematurely
- babies with heart or lung conditions or weakened immunity
Ask your doctor about RSV antibody protection for your baby, or the RSV vaccine during pregnancy.
When to talk to your doctor
- any of the warning signs above
- fever of 38°C or higher in a baby under 3 months
- symptoms getting worse after day 5
- your baby is in a higher-risk group and develops cold symptoms
Frequently asked questions
How long does bronchiolitis last?
Most babies improve within 2 to 3 weeks, though the cough can linger.
Is bronchiolitis contagious?
Yes. Wash hands often and keep your baby away from people with colds.
Does bronchiolitis cause asthma?
Some babies wheeze with later colds, but most do not develop asthma.
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Sources
- NHS: Bronchiolitis
- NICE: Bronchiolitis in children: diagnosis and management
- American Academy of Pediatrics, HealthyChildren.org: Bronchiolitis
This guide is general information, not medical advice. If your baby has breathing difficulty, seek medical help straight away.