The number of confirmed cases of the winter vomiting bug, norovirus, is 72% higher than at this time last year, health experts have said.
Three-quarters of a million people are thought to have contracted the bug, while The Health Protection Agency (HPA) figures estimate that some 68,000 people have caught it in the last week.
There have been 2,630 confirmed cases so far this season, but the HPA warned that for every confirmed case of the stomach bug, there are likely to be a further 288 unreported sufferers.
The means the real number could be 757,440. A spokesperson for the HPA said:
In the past week, schools from Plymouth to Fife have been forced to close after soaring numbers of children have fallen victim to the virus, while dozens of hospitals have been forced to close their wards.
There has also been a suspected outbreak of the Norovirus on board the P&O Cruise ship 'Oriana', which is on a ten-day round trip from Southampton to the Baltics.
Suffering passengers have been asked to isolate themselves in their rooms and not leave the boat for day trips.
In a statement P&O Cruises confirmed there were six passengers with symptoms of norovirus: