The number of NHS beds closed due to norovirus-type symptoms has doubled within a week but is still within expected levels, the government has said.
Department of Health data for England reveals that the average number of beds closed per day more than doubled from 720 to 1,545 between the weeks ending 11 December and 18 December.
In the same period last year, the figure rose less sharply, from an average of 1,002 beds to 1,805 between 11 and 18 December.
Wards are closed in NHS hospitals as part of steps to control the virus and stop it spreading between patients.
There are also figures available from the Health Protection Agency on the number of cases of norovirus that have been confirmed in laboratories.
Data up to 11 December, published earlier this week, showed that the weekly number of cases for norovirus in the previous three weeks were slightly below the average number for this time of year.
A spokesman for the DH said: “The levels of norovirus seen this week are well within expected levels for this time of year.
“If you are concerned and have symptoms consistent with norovirus you should call NHS Direct or the local GP practice for advice.”
Norovirus is highly contagious and can be transmitted through contact with an infected person or contaminated surfaces and objects.
The virus is known to spread rapidly in closed environments such as hospitals, schools and nursing homes.
Symptoms include sudden vomiting, diarrhoea or both, a temperature, headache and stomach cramps.
The bug usually goes away within a few days.
Although people can suffer from norovirus at any time of the year, activity increases in the winter months.
Most cases are seen between October and April.