Confirmed cases of norovirus are currently 66% higher than the five-year average before the pandemic, the UK Health Protection Agency has warned.
Most outbreaks seen in recent weeks are in care homes, the figures show, with cases in the over-65s at the highest level in over 10 years.
The figures have prompted public health officials to remind the public of how they can reduce the spread of norovirus, including good hand hygiene.
Those affected are likely to make a full recovery in a couple of days but need to take care not to become dehydrated, particularly the very young or the elderly, UKHSA said.
Increased numbers of outbreaks as shown by laboratory notifications have also been reported in schools and hospitals, the figures show.
Cases in the first two weeks of the year were also higher than normal, the surveillance report states.
Dr Lesley Larkin, UKHSA surveillance lead, gastrointestinal infections and food safety, said: ‘Norovirus levels are currently the highest we have seen at this time of year in over a decade.
‘Most reported cases are in the over 65s and we’re also seeing a rise in reported outbreaks, particularly in care home settings.
‘Please stay at home if you are experiencing norovirus symptoms and do not return to work (particularly if you work with vulnerable people or food) or send sick children to school or nursery until 48 hours after symptoms have cleared.’
NHS medical director Professor Sir Stephen Powis added: ‘The number of people in hospitals with norovirus has risen significantly in line with what we are seeing in the community and in care homes.
‘It is a really unpleasant illness to catch, but for the vast majority of people it will usually pass in a couple of days, and self-treating at home is the best way to help yourself and avoid putting others at risk.’
A version of the article was first published by Pulse