People who have already had norovirus, the winter vomiting bug, could be at risk of catching it again this season, experts from the the UK's Health Security Agency say. Data shows a different strain of the virus is on the rise and having had one strain doesn't necessarily protect you from catching another,

If you have the norovirus, you'll likely not experience respiratory symptoms such as congestion and a cough according to Doctor Stuart Ray, a professor of medicine and oncology at Johns Hopkins University School of Medicine. Having a headache, sore throat and cough are symptoms that “differentiate norovirus from influenza,” Martinello adds.

The effects have been particularly severe in hospitals and care homes, with cases highest among people aged 65 and over

This latest warning follows new data which shows a shift in circulating strains as norovirus spreads across the UK. Laboratory reports have now reached their highest levels since

Health leaders have warned of a “potential second norovirus wave” – with people catching the vomiting bug more than once. The UK Health Security Agency (UKHSA) said people who have already had the virus this winter could be at risk again due to a shift in which strains are becoming dominant.