A stomach bug has swept through four hospitals in Devon and Cornwall forcing staff to close wards and cancel operations.

Nine wards have been closed and all routine operations cancelled at Derriford Hospital in Plymouth where 145 members of staff and 175 patients have fallen ill.

A further 13 patients and six members of staff have been infected at the Mount Gould hospital, also in Plymouth.

The Norwalk-like virus, also known as the winter vomiting virus, causes projectile vomiting and diarrhoea and usually lasts for around 24 hours.

Rapid spread

Consultant microbiologist Dr Jim Greig said; "This virus has continued to spread rather rapidly throughout the trust and we are taking a number of additional measures to try to stem the spread."

Ten beds have been closed on an elderly care ward at the Royal Cornwall Hospital in Truro, where 15 patients and some staff have symptoms of the virus, which first struck a week ago.

Spokeswoman Laura Mason said they hoped to be back to normal within four days.

She said: "At the moment it seems as though it has been contained within that ward and we are hoping it will remain that way."

Infected

"It is an elder care ward but no patients are critically ill or giving us any major cause for concern."

The virus can be brought into hospitals by visitors or staff but there is no evidence of any link between the cases at the four hospitals.

No new patients are being admitted on four wards at Torbay Hospital, where fifty patients and at least 20 staff have been infected in the past week.

Dr Paul Turner, the hospital's consultant microbiologist, said the bug was not rare but it usually struck in the winter.

He said: "We are hoping we are over the worst of it now and we are making plans to open the wards later in the week."