THE potentially fatal superbug MRSA is becoming more widespread at Southampton General Hospital, it has been revealed today.

Hospital bosses have admitted they do not know the exact number of patients affected on their wards.

MRSA - methicillin resistant staphyloccocus aureus - is passed on by hand and can cause fever, blood poisoning and pneumonia if left untreated. It can also kill people with weak immune systems.

The Daily Echo revealed in later editions on Tuesday that four people in the hospital's intensive care unit had been struck down with the infection.

One of these patients has since recovered from the bug and been discharged from the unit, but three others in the cardiac intensive care unit are now also infected by the bug.

It is believed the number of cases is now at least in double figures, but hospital spokesman Marilyn Kay said it was impossible to reveal the exact number of patients infected.

She said: "I can't give a snapshot figure. We don't keep a running tally because it's being treated as part of people's whole clinical treatment.

"We have to take patients in, even if we know they're MRSA positive, because of their other treatment. Their treatment is more important than the MRSA.

"We have cases all of the time, like everybody else, but a lot of those would be carriers. Some of them are a problem and some are not a problem. It doesn't always affect people so they know it, so some are being treated and some are not being treated."

She added: "We don't screen every single person that comes in because it's not practical. We see immense numbers of patients passing through this hospital.

"We screen people who we suspect may have the bug. - for example, if someone's coming to us from a nursing home or from a community hospital."

Patients in the intensive care unit and cardiac intensive care unit have been separated from the other patients on those wards and are being "barrier-nursed", meaning staff and visitors are required to wear plastic aprons and gloves to prevent the spread of infection.

Mrs Kay said: "None of the patients acquired the bug in the intensive care unit and there is no problem with the intensive care department and it is not closed to admissions.

"In the cardiac intensive care unit they've got three MRSA patients and one who's a high risk because he's very ill with other things and he's been in contact with the other patients who have MRSA.

"They've opened up the high dependency intensive care beds and they've staffed it. Things are expected to be back to normal on Monday.

"We are very proud of the staff in the intensive care unit because they've taken appropriate action to stop an outbreak."

The latest figures the hospital was able to provide date back to April, when 77 of the 11,000 patients were infected with MRSA.