article in the Telegraph
"People who have been ill are being asked to stay away from hospitals in an attempt to keep wards operating normally and stop patients who are already ill and vulnerable from contracting it.
GPs have also urged people to stay at home and not visit the surgery if they get symptoms unless they are elderly, very young or have long-term illnesses, as this spreads the bug further.
The winter vomiting bug has taken hold at the same time seasonal flu is now circulating meaning health services will be under extra pressure over the Christmas period.
The norovirus bug is not normally dangerous but is extremely contagious and can spread rapidly through wards, classrooms, hotels and cruise ships.
It causes violent sickness and is most common through the winter months.
Professor Steve Field, president of the Royal College of General Practitioners said if people stay at home and drink plenty of fluids the spread of the bug can be minimised.
He said: "Obviously we worry about very young babies, the very old and people who are immunocompromised, but generally you do not need to go and see your doctor."
Thorough hand washing after using the lavatory is vital to halt the spread and frequent hand washing and disposing of tissues after use also helps to prevent others catching flu.
Last year saw record levels of norovirus with an estimated five million people struck down as the season started abnormally early and lasting into February.
This year is not expected to be as bad and since July there have been 1337 cases confirmed by laboratory testing carried out by the HPA, compared with 1661 cases confirmed in the same period last year."
You can boost your immunity to infection by cutting down on salt and salty food.