The number of NHS beds closed due to norovirus-type symptoms has more than doubled in a week, figures show.
Department of Health data for England reveals the average number of beds that were closed per day, due to diarrhoea and vomiting or norovirus-like symptoms, rose from 720 to 1,545 between 11 December 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 (HPA) 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.
Norovirus is highly contagious and can be transmitted through contact with an infected person or contaminated surfaces and objects.
Symptoms of the virus, which is known to spread rapidly in closed environments such as hospitals, schools and nursing homes, 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.