Respiratory Syncytial Virus (RSV)

We’re seeing an increase in severe respiratory illness in children as restrictions ease and people mix more, with cases higher than usual for this time of year and further increases expected over winter months.

Parents are encouraged to look out for symptoms of severe respiratory infection in at-risk children, including a high temperature of 37.8°C or above (fever), a dry and persistent cough, difficulty feeding, rapid or noisy breathing (wheezing).

While respiratory infections are common in children, last winter saw much fewer infections in younger people due to COVID-19 restrictions. This means that many will not have developed immunity and may be at higher risk of severe illness. We may also see more cases than in a typical season.

For the majority of children, these illnesses will not be serious and they will soon recover following rest and plenty of fluids.

Most cases of bronchiolitis are not serious and clear up within 2 to 3 weeks, but parents should contact their GP or call NHS 111 if:

  • Their child struggles to breath.
  • Their child has taken less than half their usual amount during the last 2 or 3 feeds, or they have had a dry nappy for 12 hours or more.
  • The child has a persistent high temperature of 37.8C or above.

Some children under 2, especially those born prematurely or with a heart condition, can suffer more serious consequences from these common respiratory infections.

Find out more about the symptoms and what to do here.


How many cases are expected this year?

In England between 2007 and 2012, there were an estimated annual average of around 33,500 hospitalisations attributed to RSV in children aged under age 5 and on average.

Cases and hospitalisations RSV infections may exceed those seen in previous years by between 20-50%.

How many deaths are there from RSV?

RSV causes 25 deaths in children each winter.

Who is most at risk of severe illness?

Children can be at higher risk of severe illness from common respiratory infections like RSV.

Most cases are not serious and clear up within 2 to 3 weeks, but the symptoms can be very worrying for parents.

For some infants and babies, such as those born prematurely or with a heart condition, respiratory infections can be more severe. NHS 111 or your GP can offer advice if any parent has concerns.

It is perfectly okay for parents to ask people with colds to keep away from newborn babies, particularly in the first two months, and for babies born prematurely.

How transmissible is RSV?

RSV is a very common virus seen that usually spreads widely in the autumn and winter months.

It is highly infectious, which is why it’s important to stick to basic hand and respiratory hygiene practices to help prevent it spreading.

What was last year’s season like?

Levels of respiratory illness were lower than average last year as COVID-19 restrictions gave the virus less opportunity to spread.

This means that many people, especially young children will have “missed” having an infection and not developed immunity.

We are seeing higher levels of RSV at the moment as restrictions ease and people mix more, and we expect levels to stay high as we progress into the autumn and winter months.

What is available in terms of medical prevention and intervention?

Good respiratory and hand hygiene practices will prevent the spread of respiratory infections such as RSV.

This means washing your hands regularly, using a tissue to catch coughs or sneezes and washing your hands afterwards, and staying away from others if you feel unwell.

How do you discern the difference in symptoms between COVID and RSV/flu?

The early symptoms of respiratory infections like bronchiolitis are similar to those of a common cold, such as a runny nose and a cough.

Further symptoms can develop over the next few days, and may include:

  • a slight high temperature (fever)
  • a dry and persistent cough
  • difficulty feeding
  • rapid or noisy breathing (wheezing)
  • parents should seek emergency NHS care if their child become breathless – the most common symptom of severe RSV.

Most cases of bronchiolitis are not serious, but you should contact your GP or call NHS 111 if:

Dial 999 for an ambulance if:

  • your baby is having difficulty breathing.
  • your baby’s tongue or lips are blue.
  • there are long pauses in your baby’s breathing.

If your child has any of the COVID-19 symptoms – a high temperature, a new, continuous cough or a loss or change to sense of smell or taste – then you should book them a test.

Does the relaxing of restrictions mean that people have been put at greater risk of other severe respiratory infections?

It is normal and expected for other respiratory viruses to circulate every year.

After a season of low numbers of respiratory viruses such as flu, it is expected that we will see higher numbers of respiratory viruses as restrictions ease and people mix more.

Good respiratory and hand hygiene behaviours will prevent the spread of COVID-19 and other seasonal respiratory illness.

There are robust systems in place to track and predict the spread of other seasonal respiratory infections and put preventative measures in place accordingly.

PHE is working with NHS England to raise awareness about the increased spread of common viruses like RSV that could pose a bigger threat over the coming months.


What causes bronchiolitis?

Bronchiolitis is caused by a virus known as the respiratory syncytial virus (RSV), which is spread through tiny droplets of liquid from the coughs or sneezes of someone who’s infected.

The infection causes the smallest airways in the lungs (the bronchioles) to become infected and inflamed.

The inflammation reduces the amount of air entering the lungs, making it difficult to breathe.


Who’s affected?

Around 1 in 3 children in the UK will develop bronchiolitis during their first year of life. It most commonly affects babies between 3 and 6 months of age.

By the age of 2, almost all infants will have been infected with RSV and up to half will have had bronchiolitis.

Bronchiolitis is most widespread during the winter (from November to March). It’s possible to get bronchiolitis more than once during the same season.


Treating bronchiolitis

There’s no medication to kill the virus that causes bronchiolitis, but the infection usually clears up within 2 weeks without the need for treatment.

Most children can be cared for at home in the same way that you’d treat a cold.

Make sure your child gets enough fluid to avoid dehydration. You can give infants paracetamol or ibuprofen to bring down their temperature if the fever is upsetting them. 

About 2 to 3% of babies who develop bronchiolitis during the first year of life will need to be admitted to hospital because they develop more serious symptoms, such as breathing difficulties.

This is more common in premature babies (born before week 37 of pregnancy) and those born with a heart or lung condition.


Preventing bronchiolitis

It’s very difficult to prevent bronchiolitis, but there are steps you can take to reduce your child’s risk of catching it and help prevent the virus spreading.

You should:

  • wash your hands and your child’s hands frequently
  • wash or wipe toys and surfaces regularly
  • keep infected children at home until their symptoms have improved
  • keep newborn babies away from people with colds or flu
  • avoid smoking around your child, and do not let others smoke around them

Some children who are at high risk of developing severe bronchiolitis may have monthly antibody injections, which help limit the severity of the infection.