The UK is being warned of a rise in a potentially serious virus, with pregnant women urged to get a vaccine to protect themselves.

Respiratory Syncytial Virus (RSV) is a common cause of coughs and colds, with most children getting an RSV infection at least once before they turn two years old.

However, it can cause "serious breathing problems", and following a record number of RSV cases in Australia, the UK is being warned over a similar rise here.

NHS officials said that the Australian winter is often a good predictor of how viruses will spread in England.

Respiratory Syncytial Virus (RSV) infections are described as "very common" by the NHS , but can cause serious illness in the elderly and young children.

Despite typically being unserious, some babies and adults have a higher risk of getting seriously ill from RSV.

The virus is a common cause of a type of chest infection called bronchiolitis in babies, which can cause breathing problems and may need to be treated in hospital.

There is a vaccine for RSV, which, as the NHS explains, is recommended if:

Last week, the UK Health Security Agency published data showing the efficacy of the vaccine.

It was revealed that the jab for pregnant women can prevent 72% of hospital admissions for their babies.

Meanwhile, the UKHSA said the vaccine is 82% effective at preventing hospital admissions for RSV among older adults.

The NHS says symptoms of an RSV infection typically start within a few days of getting infected.

Most people only get cold-like symptoms, such as:

It says that babies with RSV may also be irritable and feed less than usual.

However, if the virus leads to a more serious infection (such as pneumonia or bronchiolitis), it may also cause:

Health experts have warned that the UK should brace for a surge in RSV following a record number of cases in Australia.

Officials have said that cases have been steadily increasing in England since the start of 2025, and NHS England has urged pregnant women to get the vaccine to protect newborn babies.

It said that the virus is a leading cause of death among babies and the main cause of hospital admissions for children.

Kate Brintworth, chief midwifery officer for NHS England, said: "While for most adults RSV only causes mild, cold-like symptoms, for older adults and young children it can lead to serious breathing problems that can end up in hospitalisation.

"Getting vaccinated while pregnant is the best way to protect your baby from the moment they are born, and now is the time for mums to act, to make sure their babies are protected ahead of their first few months this winter, when there tends to be more bugs circulating."

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Pregnant women can get the jab from 28 weeks of pregnancy onwards through their maternity services or GP surgery.

Older adults aged 75-79 are also eligible for the jab.

NHS England will start inviting people to come forward in the next few weeks.