A hospital has closed all its wards to visitors in a bid to stem a “significant outbreak” of the winter vomiting bug.

A total of 140 patients and 20 staff at the Royal Lancaster Infirmary have been affected by symptoms of norovirus.

Bosses at the University Hospitals of Morecambe Bay Trust made the decision on Wednesday and said the ban would stay in effect for at least two days.

In a statement, the trust said: “In order to try to resolve a significant outbreak of norovirus at the Royal Lancaster Infirmary, UHMBT has had to make the difficult decision to close all wards to visitors in the hospital, for at least the next 48 hours.

“Despite every effort by the trust, the highly contagious winter bug has continued to spread, now affecting seven wards.”

Chief operating officer Juliet Walters said: “Whilst we understand that this may seem drastic to some people, our usual infection control methods need to be supplemented with the assistance of the public to help control and resolve the outbreak.

“It has been widely reported that the levels of this bug are 83% higher nationally than last year. There is also a huge increase of the bug in the community and we believe that members of the public who are coming into the hospital, carrying the bug or similar bugs - sometimes without knowledge - may be contributing to the problem.

“By reducing the number of people coming into our hospital, we can reduce the risk of norovirus spreading to further wards.

“This decision has not been taken lightly as we know it will be frustrating for people who have friends and family in hospital but we have a duty of care to protect the well-being and safety of our patients and staff, and this has to be our main priority.

“Our staff are working extremely hard to deal with this outbreak quickly and this decision will help us return services to normal as soon as possible. To help us achieve this, we would appreciate the co-operation of the public.”

On Wednesday, health officials said almost 880,000 people could have been affected by the norovirus outbreak.

The number of laboratory-confirmed cases of norovirus is 83 per cent higher than the same time last year, the Health Protection Agency (HPA) said.

So far this season there have been 3,046 confirmed cases of norovirus in England and Wales, but for every reported case there are likely to be a further 288 unreported sufferers, the HPA added.

Last season there were just 1,669 cases.

Norovirus is highly contagious and can be transmitted through contact with an infected person or contaminated surfaces and objects. It is known to spread rapidly in closed environments such as hospitals, schools and nursing homes.

Symptoms include sudden vomiting, diarrhoea, or both, a temperature, headache and stomach cramps. The bug usually goes away within a few days.