Bronchiolitis in Babies: RSV Winter Wheeze and Warning Signs
Bronchiolitis in babies is a winter chest infection, most often caused by RSV, that starts like a cold and then brings a cough, fast or noisy breathing and trouble feeding, usually at its worst between days 3 and 5. Most babies get through it at home with feeding support and a clear nose, but a baby who is struggling to breathe, has pauses in breathing, turns blue or grey, or is feeding far less than usual needs a doctor urgently.
What parents need first
- Who gets it: babies and children under 2, mostly under 1.
- Worst days: 3 to 5. The cough can last about 3 weeks.
- Your best gauge: feeding and wet nappies, more than the noise.
- Home care: small frequent feeds, saline drops, gentle suction, flat back sleeping.
- Emergency: grunting, chest sucking in under the ribs, breathing pauses, blue or grey lips, floppy and hard to wake.
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What is bronchiolitis, and why does it peak in winter?
The bronchioles are the tiniest airways in the lungs. In a baby they are narrower than a strand of cooked vermicelli. When a virus such as RSV (respiratory syncytial virus) infects them, the lining swells and fills with mucus. In an adult it’s a cold. Nothing more. In a small baby, those swollen tubes make breathing hard work, and the wheeze or crackle you hear is air squeezing through.
RSV spreads in coughs, sneezes and on hands and surfaces, and like other winter viruses it circulates most when families crowd indoors with windows shut. In much of Pakistan and North India that means the cold months, when an older sibling brings a cold home from school and the baby catches it.
How bronchiolitis looks at each age
- Under 3 months: the highest risk group. Signs can be subtle: feeding less, sleepier, pauses in breathing. A fever of 38 °C or more at this age always needs a doctor.
- 3 to 12 months: the classic picture: runny nose, then cough, fast breathing, wheeze, slower feeds. A fever of 39 °C or more needs a same day review.
- 1 to 2 years: usually milder, more like a heavy cold with a wheezy cough.
- Over 2: the same virus usually behaves as a cold. Repeated wheezy episodes in an older child are a different conversation with the doctor.
Babies born early, those with heart or lung conditions and those with weak immunity are more likely to get seriously ill. Babies exposed to cigarette smoke have a higher risk of severe bronchiolitis, so no one should smoke anywhere in the house.
RSV or a simple cold: how can you tell?
At first? You can’t. Both start with a runny nose and a slight cough. What separates bronchiolitis is what happens to breathing and feeding next. A cold leaves the baby feeding normally and breathing comfortably between sneezes. Bronchiolitis makes breathing faster and more effortful, the baby comes off the breast or bottle to catch breath, and feeds get shorter.
Counting breaths is the most reliable way to judge speed. The method and the age limits are set out in how to count a baby’s breathing. A harsh barking cough with a hoarse cry is more likely croup, which behaves differently; see croup at night.
Feeding is the gauge: what to watch
A baby who can’t breathe through a blocked nose can’t feed well, and a baby who isn’t feeding gets dehydrated. That’s why doctors ask about feeds first. Always.
Keep a nappy and feed tally
On a piece of paper on the fridge, tick every wet nappy and every feed with the time. Compare with a normal day. If a baby is taking much less than usual, or you have a dry nappy for 12 hours, call your doctor the same day. The tally also gives the doctor exact facts instead of “she’s not eating much”.
Home care that actually helps
- Offer smaller feeds more often. Breast or formula only. Under 6 months, nothing else: no water, gripe water, ghutti, herbal drops or honey (and never honey under 1 year).
- Clear the nose just before a feed. Use saline drops: half a level teaspoon of salt in 250 ml of boiled and cooled water, or a pharmacy saline. Put 2 or 3 drops in each nostril, wait a minute, then gently use a bulb sucker or nasal aspirator at the nostril opening only. Doing this before, not after, a feed is what gives the baby a clear nose to drink through.
- Keep the baby upright while awake and while feeding. Hold them on your shoulder or sit them in your lap.
- Sleep flat on the back in a bare cot. Never prop the mattress, tilt the cot on books or add pillows, whatever the cough. Safe sleep rules don’t change during an illness.
- For fever or discomfort, ask a pharmacist or doctor; children’s paracetamol is given by weight from the pack, and never combined with another product containing the same medicine.
- Keep the air clean: no smoking indoors, no angithi or coal heater in a closed room, and air the room daily.
If you’re thinking about steam, read humidifier vs steam bowl first; a bowl of boiling water near a baby is a serious scald risk.
Suck the nose, then feed. Not the other way round.
Do nebulisers, antibiotics or cough syrups help?
The NHS states there is no specific treatment for bronchiolitis. It is caused by a virus, so antibiotics don’t help unless a doctor finds a separate bacterial infection. The reliever nebulisers that help asthma usually don’t make much difference in typical bronchiolitis in babies, which is why many doctors don’t use them routinely; the decision is the doctor’s. If one is prescribed, the nebuliser technique guide explains mask fit.
Over the counter cough and cold medicines are not for children under 6. Vicks, camphor, menthol, eucalyptus and mustard oil with camphor should never go on or near a baby, chest included. In hospital, the help that matters is oxygen if levels are low and feeding support through a tube or drip, which is exactly what a struggling baby needs.
If your baby is grunting, the tummy or chest sucks in under the ribs with each breath, there are pauses in breathing, the lips, tongue or skin look blue or grey (on darker skin check the lips, gums, palms and inside the eyelids), or the baby is floppy and won’t wake or stay awake. See a doctor the same day if feeds are much less than usual, there’s a dry nappy for 12 hours or other signs of dehydration (no tears, sunken soft spot), a baby under 3 months has a temperature of 38 °C, an older baby has 39 °C or more, or things are getting worse after day 3 to 5. Trust your judgement: if you feel your baby is seriously unwell, go.
More cold season guides are gathered in Season Shift.
Bronchiolitis questions parents ask
What are the symptoms of bronchiolitis in babies?
It starts with a runny nose and mild cough, then fast or noisy breathing, wheeze or crackles, trouble feeding and irritability. It is usually worst on days 3 to 5.
How long does bronchiolitis last?
Most babies improve after the first week, but the cough can last around 3 weeks. Return to the doctor if things get worse instead of better.
When should I take my baby to hospital for breathing?
Immediately for grunting, chest sucking in under the ribs, pauses in breathing, blue or grey colour, or a floppy baby who is hard to wake.
Is a nebuliser good for bronchiolitis?
Often not. Reliever nebulisers usually make little difference in typical bronchiolitis, so doctors decide case by case. Don’t use one at home unless it was prescribed.
Can my baby sleep propped up with a blocked nose?
No. Babies must sleep flat on their back in a bare cot. Hold your baby upright while awake instead, and clear the nose before sleep.
Does my baby need antibiotics for RSV?
Usually not, because RSV is a virus. A doctor may prescribe them only if a bacterial infection is also found.
Can I put Vicks on my baby’s chest?
No. Vicks, camphor, menthol and eucalyptus products should never be used on or near babies and young children.
How can I tell RSV from a cold?
Early on you can’t. Watch breathing and feeding: faster, harder breathing and shorter feeds point to bronchiolitis rather than a simple cold.
Can bronchiolitis come back?
Yes, children can catch RSV again, though later infections are usually milder. Some babies wheeze with colds for a while afterwards; mention it to the doctor.
How do I stop my baby catching RSV?
Wash hands before handling the baby, keep anyone with a cold from kissing the baby’s face, avoid crowded rooms in winter and keep the home smoke free. Ask your doctor whether any RSV protection is available locally.