Baby · Health

RSV and Your Baby: What UK Parents Need to Know This Winter

RSV is the main reason babies end up in hospital with bronchiolitis every winter, and it is also the one respiratory virus you can now do something about before your baby is even born. Here is the calm, practical version.

By Katie Manson  ·  6 min read

Every autumn, the same virus fills children's wards across the UK. RSV, respiratory syncytial virus, is so common that around nine in ten children catch it before their second birthday. For most it looks like a heavy cold. For some babies, especially those under six months, it travels down into the smallest airways and becomes bronchiolitis, which is why RSV season, roughly October to February with a peak in November and December, is the busiest time of year for baby A&E visits. Last winter alone, children with RSV accounted for almost 7,000 hospital bed days in England.

None of that is written to frighten you. It is written because RSV is predictable, and predictable things can be prepared for.

What RSV looks like in a baby

It starts like a cold: runny nose, cough, mild temperature, off their feeds a little. Most babies stay at that level and recover within a fortnight with the usual cold care, feeds little and often, saline drops and a snot sucker if you can face it, paracetamol for babies over two months if they are uncomfortable and it is suitable for them.

The thing to watch is the breathing. Bronchiolitis tends to worsen around day three to five, so a baby who seems to be turning a corner and then starts working harder to breathe is a baby who needs looking at.

When to get help

Trust yourself here, you know your baby's normal. Contact your GP or call 111 if your baby is taking fewer than half their usual feeds, has had a dry nappy for 12 hours or more, is breathing fast, has a temperature of 38C or above under three months (or 39C and over at three to six months), or just seems unusually tired and irritable. Call 999 if your baby is struggling to breathe, grunting, sucking in at the ribs or tummy, going blue or grey around the lips or tongue, or has pauses in their breathing. The NHS page on bronchiolitis lists these signs in full and is worth two minutes of your time before the season starts, for the same reason we all read the baby first aid guide: calm parents are made in advance.

Colds are for riding out. Breathing is for acting on.

The RSV vaccine in pregnancy

This is the newest tool in the kit and the one many parents still have not heard about. Since late 2024, every pregnant woman in the UK has been offered the RSV vaccine from 28 weeks of pregnancy. Your body makes antibodies and passes them across the placenta, so your baby is born already protected during the months they are most vulnerable. NHS figures show babies whose mothers were vaccinated at least two weeks before delivery are around 72 per cent less likely to be hospitalised with RSV.

The window matters: from 28 weeks is ideal because it gives antibodies time to cross before birth, though the vaccine can be given right up to delivery, and it is especially worth prioritising if your baby is due between late summer and midwinter. Ask your midwife at your next appointment, or book through your GP surgery. The official factsheet covers the details if you like your information with references.

Everyday protection that actually helps

For babies already here, the boring basics do real work. Ask anyone with even a hint of a cold to admire the baby from a distance, and that includes relatives who insist it is just sniffles. Wash hands before cuddles. Keep your baby's world smoke free. Wipe down toys and surfaces when older siblings, the usual delivery route for RSV, come home streaming from nursery. You will not block every germ, and you do not need to. You are buying time and lowering the dose, and with RSV both of those matter.

And if the winter evenings with a coldy, clingy baby are stretching you thin, that is not a failure of parenting, it is the witching hour with a head cold on top. Lower the lights, lower the bar, and get through to bedtime.

This article is general information, not medical advice. For your own baby, always follow the advice of your midwife, health visitor or GP, and use the NHS bronchiolitis page for the full list of warning signs. In an emergency, call 999.