The Royal Free Hospital has been hit by one of the worst outbreaks of the winter vomiting bug in the country.
The hospital in Pond Street, Hampstead, has been forced to close three of its wards in a bid to stem the spread of the norovirus.
More than 130 beds were out of action at the end of last week, according to figures from the Health Protection Agency.
Another ward has also been affected.
During last year’s outbreak in December three wards were closed at the Royal Free, with 50 patients affected by the virus.
Up to a million people across the country are struck down by the virus every year.
The usual symptoms are sudden vomiting, diarrhoea, headache and a temperature.
While not life-threatening, the norovirus can often lead to severe dehydration in the elderly and very young.
The Royal Free has asked those suffering from the symptoms to steer clear of the Accident and Emergency ward in a bid to curb the spread of the virus. Instead, sufferers are asked to call NHS Direct 0845 46 47 or their GP.
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