Rogue bacteria blamed for three baby deaths

Microbiologist Mark Jones (left) and Michael Hewson, consultant in neonatal medicine, speaking to the media yesterday. Picture / Fotopress

Three babies have died after being infected with an aggressive strain of bacteria in Wellington Hospital's intensive care unit for premature babies and strict isolation measures have been put in place to try to eradicate the bug.

The hospital said last night the babies had died in the past few months and a total of 37 babies had been infected since the strain was detected late last year.

The bug is a rogue strain of the reasonably common Staphylococcus aureus bacterium, which doctors said had been particularly aggressive in infecting the very vulnerable young babies in the neonatal intensive care unit.

Those premature babies are just the size of a hand when born at 24 to 27 weeks and are prone to sometimes fatal infections.

Wellington Hospital has not yet decided if it will move any babies to other units, but it is likely to look to Auckland and Waikato Hospitals if it needs help.

In the meantime, it is admitting only babies from the Wellington region. Babies from Hawkes Bay, the Manawatu and top of the South Island are likely to be sent to other hospitals.

Wellington is also facing a nursing shortage in its specialist unit, after six nurses were confirmed through tests as carrying the new bacterial strain. They will be off work for up to three weeks.

Hospital microbiologist Dr Mark Jones said those six nurses were "extremely distressed" knowing they had been in the unit while carrying the organism. But they were not the cause of the deaths.

"They are absolutely desperate. It's hard. You can never remove the doubt from caring nurses."

The hospital is still admitting premature babies to the unit and no babies there at the moment have severe infections.

Infected babies may be treated with antibiotics, with a response noticeable after just 24 hours.

Very vulnerable babies have been placed under close watch for symptoms of the bacterium, which can include conjunctivitis or skin infections.

Neonatal consultant Dr Michael Hewson said he could not say that no other baby would die.

But Staphylococcus aureus was one of the top three fatal infections for premature babies, and no hospital could provide a unit that had a zero rate of infections.

"The babies we have that are currently infected and being treated are doing well," he said.

Staff were providing extensive information to families who had a baby in the unit.

Babies already discharged were not at risk.

The strain of the infection was identified from the blood of the three babies before they died, and although it had been hard to contain it was not resistant to treatments.

Of 25 babies in the Wellington neonatal unit, eight are infected. Six staff are off but 15 have been found to be carrying the organism.

Three were linked to the rogue strain and all suffered blood poisoning. All staff who test positive for the new strain of Staph. aureus will be taken off clinical duties.

Restrictions put in place to try to eradicate the organism include introducing isolation areas in the unit, allowing only parents and not extended families to visit babies and treating staff. The hospital is also seeking international advice.

Dr Jones said it was not known why a new strain had attacked the unit and it probably would never be known how it developed. It might be an accident of genetics which had made it more difficult to eradicate.

The infection was not present anywhere else in the hospital.

The hospital says it treats between 750 and 800 babies in the neonatal unit each year and, despite strenuous efforts, 25 to 30 die. It may be another month before the hospital is fully operational again.

One man, whose babies had recently been in the Wellington unit, said swabs were taken for infection but he was not told there was an ongoing problem there.

He felt "disappointed" at not being told what was happening, or even being told the results of the swabs.

His main concern now was trying to establish the symptoms of the infection and what to do if they arose.

Midwife Ann Noseworthy said the Wellington neonatal unit was known for its "very strict" regulations regarding hygiene and public access to the babies.

"Their practices are very good. It's just terribly unfortunate that this bug has turned up there." 

Dr David Knight, clinical leader of National Women's at Auckland City Hospital, said every hospital and unit had special infection control procedures which helped to prevent the bug and detect it quickly.

There was no need for Auckland neonatal intensive care units to step into crisis mode or take extra measures, because the bug was particular to Wellington Hospital.

Dr Knight said Starship and other hospitals with neonatal units would consider it if needed.

Health Minister Annette King said she was briefed by Capital Coast Health chief executive Margot Mains last night.

"I have also asked for a full briefing - what they have been doing and the background to it - to be on my desk by [this] morning and she has promised I will have it."

Ms King said it was not unusual that she had only just been informed about the deadly bacteria despite the hospital knowing for six months.

"Outbreaks of these sorts of bugs are common around the world and I don't necessarily get told about all of them.

"Infection control in New Zealand is of an incredibly high standard."

DANGEROUS BUG

Staphylococcus aureus is a common infection but difficult to treat because different strains have developed a resistance to commonly used antibiotics.

The Wellington Hospital strain can be treated with flucloxacillin.

Up to 30 per cent of people carry Staph. aureus bacteria on their skin. These are usually harmless but can cause boils, skin abscesses, wound infections, blood infections and pneumonia.

It is spread by touching. It can survive on bedding, towels and benches, so bad hygiene and crowding can exacerbate its spread.

Infection can be serious or fatal for those with suppressed immunity, such as the elderly and the sick, so can be devastating once in a hospital or rest-home.

additional reporting: Claire Trevett, Ainsley Thomson, Elizabeth Binning