Hospital's superbug crisis

The district health board is now considering extreme measures to cope with the ESBL superbug outbreak, including splitting hospital wards. Photo / Paul Estcourt

A superbug outbreak at a major hospital has become so serious that officials are considering splitting wards into two sections.

One section would be for people with the bug, and the other for those who don't have it or are awaiting test results.

Up to one in five patients at North Shore Hospital are contracting the ESBL superbug, about 70 per cent of them while in hospital.

It is usually carried in the bowel but if it crosses into the blood it can be fatal.

In the nine months to April, the Waitemata health region - in which North Shore is the main hospital - had five deaths linked to the bug.

The district health board is now considering extreme measures to cope, including splitting hospital wards.

This plan would increase the hospital's staffing costs.

Patients are already divided into "red" rooms for those who test positive, "amber" rooms for those awaiting results and "green" for patients who have been cleared.

New Zealand's number of ESBL cases has risen sharply from nearly zero in 1999 to more than 5000 last year. The worst affected regions are Auckland and Hawkes Bay.

The bug exploded into the Waitemata board's area in 2007, when the monthly total reached 115 hospital patients who tested positive.

At its peak, in April, the total was 245 - more than one in five patients.

North Shore Hospital is worse affected than Waitakere Hospital.

One of the most worrying aspects is that about 70 per cent of positive cases catch the bug in hospital. It is thought staff inadvertently transfer the bacteria during normal healthcare procedures.

Improved hygiene measures are credited with cutting the tally to 162 in August.

ESBL - extended spectrum beta lactamase-producing bacteria - are resistant to a range of antibiotic drugs.

They live mainly in the bowel and sometimes in the bladder.

Most of the positive patients are "colonised" - carriers who are not harmed by the bug and do not need to have it treated.

But if it crosses into the blood stream, it can cause a serious infection and sometimes death.

Waitemata had 13 ESBL blood-infection cases between August last year and April. Five died.

The chief medical officer, Associate Professor Johan Rosman, said the deaths were of patients aged more than 70 who had a variety of serious illnesses.

Although they had ESBL, it was not the cause of death.

After case numbers shot up from September last year, the health board sought help from the US Centres for Disease Control and Prevention.

They sent a team of investigators, who recommended that North Shore Hospital, a tower block, be reconfigured to put positive and negative cases on separate floors.

Professor Rosman said this was not possible, so the board was considering splitting each medical and surgical ward into two parts, each with its own nursing staff.

Under the hospital's present system, staff wear gowns, gloves and sometimes masks in the red and amber rooms.

Red-room staff are generally meant to work only in those rooms, but shortages sometimes mean they also have to work in amber rooms.

Professor Rosman said managing the outbreak was costly because of the need to test every patient and the more complex staffing and cleaning arrangements.

Part of the problem was that North Shore Hospital was "old" - 25 years old - which meant it was harder to clean and provided less space for each patient than newer facilities.

The Auckland and Counties Manukau district health boards also have nationally high rates of ESBL.

But their rates are lower than that of Waitemata, and they screen only patients considered at increased risk of carrying the bug.

Professor Rosman said the world's superbug problems were "the consequence of our decades of over-treatment with antibiotics".