STAFF at Frimley Park Hospital have this week urged the public to avoid visiting patients on the wards "unless absolutely necessary," following an outbreak of norovirus. Twenty-seven beds in four bays and three single rooms have been quarantined to deal with the infection, although not all patients in the bays were affected with the virus. Also known as the winter vomiting bug, norovirus causes diarrhoea and vomiting accompanied by flu- like symptoms such as fever or chills and usually lasts for no longer than 48 hours. The hospital warns that it is difficult to stop the norovirus from entering hospitals, as it is not possible to prevent patients being admitted who are already ill with it. Once inside it can spread rapidly and members of staff at the hospital have been affected as well as patients. Anyone who does feel the need to visit the hospital is being reminded that observing the visitors' code of conduct will minimise any risk of infection. Mary Dune, director of nursing, quality and patient services, said: "At present we appear to have the norovirus contained but because it can spread so easily the situation can change rapidly. "Public co-operation really can make a big difference and although it rarely results in any long-term effects, it can be very unpleasant for patients, visitors and staff who have it." Hand cleansing has been singled out as the most effective means to prevent the spread of any infection and those who feel it necessary to visit are being told to use the hand gel each time they enter and leave a ward. Children under 10 should not visit the wards, according to the advice issued this week, and anyone who is unwell or has been unwell in the past 48 hours should also stay away. Mary Dune added: "The hospital is not turning away sick patients who require urgent treatment but the public can help us contain the virus by not coming to visit patients unless absolutely necessary." Anyone who has been unwell with diarrhoea and vomiting accompanied by flu-like symptoms and have an outpatient appointment at the hospital is being advised to call the hospital on 01276 526440.