Westmead researchers harnessing viruses to kill super bugs

Senior Staff Specialist Infectious Diseases and Microbiology Professor Jon Iredell.

Finding out how to overcome the worst bacteria threatening human health is gaining ground at Westmead Hospital in Sydney.

A team of researchers led by Professor Jon Iredell is cautiously optimistic it can one day help beat infections such as golden staph.

Professor Iredell’s lab is based at both the Research and Education Network (REN) and the Westmead Institute for Medical Research (WIMR).

“It’s the only site in the world that we know of that is doing this work,” Professor Iredell told The Pulse.

The aim is to use the viruses that normally destroy bacteria out in nature to treat humans who are infected with those same bacteria.

“These viruses don’t cause human disease like the flu, which is a virus, these are actually viruses of bacteria,” said Professor Iredell.

“The idea is to bring in this extra natural predator to destroy the bacteria during infection.”

Jon Iredell is an infectious diseases physician and clinical microbiologist specialising in critical infections and antibiotic resistance.

He is a Professor of Medicine and Microbiology at the Sydney Medical School, a Director at the Centre for Infectious Diseases and Microbiology, and a Senior Staff Specialist in Infectious Diseases and Microbiology at Westmead Hospital.

His groundbreaking research draws upon the simple axiom that everywhere there is a bacteria, there is a virus that infects it.

“The purpose is to identify viruses that are specific to the bacteria that you want to kill, and have them in a very pure form… and give that to patients in the same way that you would give a drug,” Professor Iredell said.

“So, it’s the natural enemy of bacteria and it’s a way to try and kill bacteria that is not currently being used.”

Early results have been promising.

Joshua Robertson was critically ill after being diagnosed with a golden staph infection, suffering a stroke and falling into a coma.

He was granted compassionate access to the trial at Westmead Hospital, and was given a bacteriophage – or phage – a bacterial virus.

His recovery has been incredible and has given researchers hope that they are on the right track.

“We have got some signals, especially from the lab data, that suggests they are going to be very effective,” Professor Iredell said.

Around a dozen patients, who are already on optimal treatment, are being administered the phage on compassionate grounds.

“This is a compassionate use where we’re thinking, I’m not guaranteeing that this will work, but it seems to be safe and it may well offer you a benefit,” Professor Iredell said.

Researchers have found the use of the phage is most effective as an

add-on to antibiotics, where the infection is so severe or so overwhelming that it’s likely antibiotics won’t be enough.

“We’re surprised by the results but we cannot honestly say to you that there is any evidence that it’s definitely a benefit, until we do one of these classic comparative studies,” Professor Iredell said.

“At the moment our main aim is to show it is safe to use, and I think we do have evidence that that’s the case, and that it may be a benefit, and I think we have evidence that that’s the case, but can I say ‘yes’ definitively? No, I can’t.

“People have actually recovered from their infection but you know, a cynic could say, well that was your antibiotics…can you prove to me that it was the viruses that made the difference? I can’t prove that, no, but yes I am very optimistic about this.

“We think the data that we’ve got justifies doing that comparison study.

“Early results are promising.”

Professor Iredell expects that one day the phage treatment will become standard for bacteria like golden staph, much like antibiotics are now.

And, he believes, it will likely be used as an add-on to antibiotics.

“I suspect once we’re able to demonstrate it is effective, it will be routinely added,” he said.

“It looks like another drug, it’s administered like another drug, the only difference is the way that it works….and this particular mechanism is just a different kind of biological attack on the organism.”

The hope is that one day the threat of golden staph will be greatly lessened or neutralised.

“All of us naturally carry it and only a few of us get a nasty infection, but when it does get in, it can cause terrible damage,” Professor Iredell said.

The phage treatment potentially has other applications: against pseudomonas – bacteria which cause complications in burns; in cystic fibrosis patients; and against two common gut bugs which are resistant to antibiotics.