Lancashire Teaching Hospitals NHS Foundation Trust has been forced to close one ward at Royal Preston Hospital and three wards at Chorley and South Ribble Hospital to new admissions because of the number of cases of winter sickness.

Ward 18 at Royal Preston Hospital is affected, as are the Lostock and Rookwood A and B wards at Chorley.

The trust is isolating patients who have the bug and new admissions are being accommodated on other wards around the hospitals.

Health chiefs say patients' friends and relatives who have been ill themselves or may have come into contact with someone who has winter sickness should stay away unless their visit is absolutely necessary.

Dr John Cheesbrough, consultant microbiologist at Lancashire Teaching Hospitals NHS Foundation Trust, said: "Winter vomiting is caused by a virus and its outbreak has coincided with the recent cold snap.

"It is very easily transmitted for one person to another in the home, at work or school and in healthcare settings such as hospitals and residential and nursing homes.

"The illness, although unpleasant, usually lasts between 24 to 36 hours. Symptoms are typically nausea and vomiting and, in some cases, diarrhoea."

Linda Parkinson, acting director of operations at Lancashire Teaching Hospitals NHS Foundation Trust, said: "We are coping with the situation and the extra demands being placed upon us.

"We would like to thank staff for their efforts and we are advising the public who have been ill themselves not to come into hospital to visit friends and relatives unless their visit is strictly necessary."

Winter vomiting disease is a sickness and diarrhoea virus and is known as the Norwalk or Norovirus.

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