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🫁 Childhood illness guide

Bronchiolitis

A common chest infection in babies, usually caused by RSV

EW

By Emma Whitfield · Pregnancy & Baby Writer

What it is

Bronchiolitis is a common chest infection that affects babies and children under 2, usually caused by a viral infection (most often RSV).

Symptoms

  • Early, cold-like symptoms: sneezing, a runny or blocked nose, a slightly high temperature
  • Progressing to: a cough, breathing more quickly, difficulty feeding or eating, noisy breathing (wheezing or crackling sounds), becoming irritable

How long it lasts

Symptoms are usually worst between days 3 and 5, and the cough usually gets better within 3 weeks.

What helps at home

  • Give children's paracetamol or ibuprofen if your child is distressed or uncomfortable
  • Keep your child upright as much as possible when they're awake, to help them breathe more easily
  • Check on them regularly, including during the night
  • Encourage fluids — give babies smaller feeds more often
  • Don't smoke around your child, and don't sponge them with cool water or remove clothing to try to lower a temperature
  • Never give aspirin to a child under 16

See a GP if

  • Your child's cold is getting worse
  • Your child is feeding or eating much less than normal
  • Your child has had a dry nappy for 12 hours or more, or shows other signs of dehydration
  • Your baby is under 3 months with a temperature of 38°C, or older with a temperature of 39°C or higher
  • Your baby feels hotter than usual on their back or chest, or feels sweaty
  • Your child has a very high or low temperature, or is shivering
  • Your child is very tired, irritable or not themselves
  • You're worried about your child

Call 999 if your child:

  • Is having difficulty breathing — you may notice grunting noises, their tummy sucking in under the ribs, or fast breathing
  • Has pauses when they breathe
  • Has blue or grey skin, tongue or lips (this may look different on brown or black skin)
  • Is floppy and will not wake up or stay awake

Contagious period & nursery/school

The NHS doesn't give a specific stay-off-nursery period for bronchiolitis — keep your child home while they're unwell, and be aware RSV spreads easily to other babies.

Bronchiolitis: common questions

What is bronchiolitis?

Bronchiolitis is a common chest infection that affects babies and children under 2, usually caused by a viral infection (most often RSV). Symptoms are usually worst between days 3 and 5, and the cough usually gets better within 3 weeks. This is general information, not a diagnosis — see a GP or call NHS 111 if you're unsure.

What are the symptoms of bronchiolitis?

Early, cold-like symptoms: sneezing, a runny or blocked nose, a slightly high temperature Progressing to: a cough, breathing more quickly, difficulty feeding or eating, noisy breathing (wheezing or crackling sounds), becoming irritable

When should I call 999 for bronchiolitis?

Call 999 if your child: Is having difficulty breathing — you may notice grunting noises, their tummy sucking in under the ribs, or fast breathing Has pauses when they breathe Has blue or grey skin, tongue or lips (this may look different on brown or black skin) Is floppy and will not wake up or stay awake

Sources & further reading

This is general information sourced from NHS.uk, not medical advice or a diagnostic tool. Every child is different — if you're at all worried, contact your GP, call NHS 111, or in an emergency call 999. Reviewed July 2026.