Two hospitals coping with a growing influx of patients suffering from a vomiting virus have been forced to restrict visiting times.
The Noro Virus is highly contagious
The Royal Berkshire and Battle Hospital in Reading, Berks, have inherited Noro Virus patients from other hospitals like Oxford's John Radcliffe Hospital.
Non-urgent surgery has been cancelled for the time being, The Royal Berkshire and Battle Hospital NHS Trust said.
People with symptoms should contact their GPs or NHS Direct, it says.
A trust spokeswoman said: "To protect others, it is important not to visit anyone in hospital until 48 hours after symptoms have ceased.
"Anyone who thinks they might have the virus should avoid contact with other people as far as possible."
The trust says it has restricted visiting to patients "as a precaution".
Visitors must now contact the nurse in charge before entering a ward.
They should not sit on beds, and should always wash their hands or use the alcohol hand rub available on entering and leaving a ward.
The Health Protection Agency says there are a million cases of this type of gastro enteritis annually.
It said most outbreaks are in confined spaces - such as hospitals - but its not that "unusual" to find the virus just spreading around in community.