Doctors are urging people who have caught the norovirus to stay at home after it emerged that cases of the vomiting bug have doubled in a year.
According to the Health Protection Agency (HPA), the number of reported cases has hit a high not seen since 2002, but it is believed the true number of people affected is actually much greater as many of those stricken by the bug do not see their GP.
Doctors estimate that more than 100,000 people a week are catching the stomach bug, which causes diarrhoea and vomiting.
And Professor Steve Field, chair of the Royal College of GPs, said the number of new cases each week may even top 200,000 across the UK.
He said that surgeries and hospitals have been deluged with people wanting advice, and urged those who have contracted the virus to stay at home, drink lots of fluids and take paracetamol.
Norovirus frequently spreads in places where people congregate, such as schools and cruise ships, and many cases also often occur in hospitals.