Cases of a potentially-fatal bug have rocketed at Oxford's John Radcliffe and Churchill hospitals, bucking a national trend.

Infection control staff at the Oxford Radcliffe Hospitals NHS Trust last night warned the onset of the cold season could be a "testing time" at the hospitals.

They spoke out after official figures showed the trust, which also oversees Banbury's Horton Hospital, saw a 38 per cent increase in cases of Clostridium difficile - known as C diff - within three months, bucking a 13 per cent decrease nationally.

Now, a dedicated ward could be set up to isolate infected patients during the winter months.

Although patients thought to have the stomach bug are immediately isolated to prevent cross-infection, the situation could become difficult if winter brings an increase in emergency admissions.

Patients who need antibiotics are more at risk of catching C diff because the medication weakens their stomachs.

Trust infection control manager Lily O'Connor said: "If we have a lot of people coming in with chest or urinary infections, we'll have to watch our C diff figures two weeks later.

"We've been quite lucky because priority is given to C diff and at the moment we've been managing it well and all patients with the bacterium are isolated.

"If we had a lot of patients with C diff we may have to dedicate one area of a ward to male C diff patients and one area to female C diff patients.

"But I'm hoping it won't come to that."

According to the Health Protection Agency, 184 ORH patients over 65 were infected with C diff between April and June this year, compared to 133 between January and March.

Mrs O'Connor admitted it was not understood what caused the peak, but added numbers were decreasing, with 127 cases between July and September and 29 cases in October.

Despite the raft of measures introduced to combat C diff, high rates of the bacteria are causing concern among members of the NHS watchdog, the ORH Patient and Public Involvement Forum.

Chairman Jacquie Pearce-Gervis said: "We're aware C diff at the trust isn't under control yet and both we and members of the public are very worried."

*If you or your relative have been affected by C diff, contact the Oxford Mail newsdesk on 01865 425405.