Bronchiolitis

A chest infection of babies, usually RSV. Most are managed at home; the thing to watch is feeding and breathing, not the cough.

What it is

A viral infection of the smallest airways in babies and children under two, most often caused by respiratory syncytial virus. It is very common, peaks in winter, and most children have had it by their second birthday.

It typically starts as a cold and moves down into the chest around day two or three, gets worse until about day three to five, and then slowly improves. The cough can last two to four weeks after everything else has settled.

Most babies are looked after at home. A minority, particularly those born prematurely, those under three months, and those with heart or lung conditions, become unwell enough to need hospital support with feeding or oxygen.

Antibiotics do nothing, because it is viral. Inhalers and steroids do not help in bronchiolitis either, which surprises parents who have seen them used for older children with wheeze.

An RSV vaccination programme now protects babies through pregnancy and protects older adults, and it has changed the winter picture substantially.

Signs you might notice

A cold for a day or two, then a cough, fast breathing and wheeze.

Feeding less: taking under about half the usual amount over two or three feeds is the most useful single measure a parent can track.

Fewer wet nappies.

A slight fever.

999 or A and E now: pauses in breathing; a baby that is very pale, blue or grey around the lips; grunting with each breath; the skin sucking in under the ribs, between the ribs or at the base of the neck; too breathless to feed; floppy, drowsy or difficult to wake; or a fever in a baby under three months.

Also urgent: fewer than half the usual feeds, or no wet nappy for 12 hours.

How it can affect day-to-day life

The illness gets worse before it gets better, which means a baby seen and sent home on day two can genuinely need bringing back on day four. Parents are often made to feel they are wasting time by returning. They are not, and saying so in advance matters.

The cough outlasting everything by weeks is normal and is the commonest reason for repeat appointments.

Smoke exposure makes it worse. Nobody wants a lecture with a sick baby in their arms, but it is a real and modifiable factor. See smoking.

Hospital admission for a few days of feeding support and oxygen is common and is not a sign anything was missed.

Supporting someone well

Small, frequent feeds rather than full ones. Keep count of feeds and wet nappies; that is the measurement that matters.

Keep the baby upright when feeding and slightly propped when settled, following safe sleep advice.

Paracetamol at the right dose for weight and age if they are uncomfortable.

Saline nose drops before feeds can make a real difference to a blocked nose.

Do not expect antibiotics, inhalers or cough medicine. None of them work here.

Take the RSV vaccination offered in pregnancy, which protects the baby for the first months.

Do not smoke around the baby, and ask visitors not to.

Go back if things are getting worse rather than assuming you have already been seen.

Where to get help

NHS 111 or a GP practice for a baby who is feeding less or breathing faster.

999 for pauses in breathing, colour change, grunting, marked chest recession, or a floppy or drowsy baby.

Asthma + Lung UK helpline: 0300 222 5800.