Superbugs: The health threat that has failed to capture public attention
COVID-19 has been a wake-up call for the world, about the need to be prepared for the sudden emergence of new and fatal global infections.
But before the coronavirus pandemic began causing sickness, pain and death, another much bigger threat has been evolving – and it needs to be stopped.
That threat is antimicrobial resistance – superbugs that have evolved to be immune to pharmaceuticals used to treat bacterial, fungal, parasitic and viral infections.
Superbugs are predicted to kill some 22,000 Australians a year within 20 years.
That’s a significantly greater number of fatalities than the coronavirus pandemic that has sent states into lockdown and businesses to the wall. Yet, somehow, the superbug threat has so far failed to capture public attention.
Read more: Antibiotics and the battle against the superbugs
Monash's Associate Professor Mark Davis, a medical sociologist, hopes the public mood is now right for people to take serious heed of superbugs.
He says Australian governments have done a good job in convincing people of the importance of taking action to protect themselves and others during the coronavirus pandemic.
“Victoria’s ‘Stand with Dan [Andrews]’ approach has worked well for the state as it went into a difficult, second lockdown,” he says. “Public awareness and action is helped with clarity, strength, consistency, constant messaging.”
Read more: Sleepwalking towards an antibiotic apocalypse
Associate Professor Davis is part of the multidisciplinary team at Monash University’s Antimicrobial Futures and Societies, which is funded by the Australian Research Council, and a member of the Monash Centre to Impact AMR.
His colleagues at the Monash Centre to Impact AMR want to deeply understand how and why antimicrobial resistance occurs, to come up with alternative solutions to stopping malicious, resistant superbugs.
These strategies include helping the body overcome infections without just firing antibiotics at the invading bug and all the good micro-organisms around it, so that we stop creating more drug-resistant infections, and can save lives without antibiotics.
Associate Professor Davis says the average Australian may know very little about AMR, or the differences between viral, bacterial and fungal pathogens, or even why, how and when antibiotics should be used.
“So it's about helping people understand why a clinician might refuse antibiotics in some situations,” he said.
One of his colleagues at the Centre to Impact AMR is biochemist and cell biologist Dr Thomas Naderer. He's also concerned that people don't understand the difference between viruses and bacteria, and that antibiotics treat bacteria and not viruses.
“Quite often we go to the doctor and assume that antibiotics will take care of common lung infections so that we can get back to work quickly,” he says. “In case of viral infections, however, antibiotics have little benefit, and their misuse promotes antimicrobial resistance.”
He's looking at host-directed therapies that don't target the superbug itself – like antibiotics do – so we don't put evolutionary pressure on them to evolve resistance.
Targeting cells is the aim
Dr Naderer says our immune system does a fantastic job of clearing infections – most of the time.
He wants to target just the cells that are hosting invading superbugs and fail to be cleared by the immune system. Keeping all other healthy cells intact will be critical to developing therapies.
“Once we understand how to do that, then we can build on the knowledge using drugs that are already available, like anti-cancer drugs that let you kill your own, bad, tumour cells.”
They’ve had successes in trials.
“We're able to kill off infected cells, and then prevent infections, not targeting bacteria at all, or healthy cells.”
He says this kind of research will become more and more important.
“We need to understand better why some people get sick and why some people just breeze through COVID or other infections. Because once we understand that, maybe then we can come up with new therapies.”
Professor Ana Traven, a molecular biologist who researches fungal superbugs at the Centre to Impact AMR, is also working on understanding how the immune system fights off infections.
“It is true that more people die from bacterial infections than fungal infections. This is absolutely the case. But still, we estimate that one-and-a-half million people every year die from fungal infections. It's not a small number of people,” she said.
“I think, you know, the public doesn't really know these facts.”
Read more: Inside us, bacteriophages fight a never-ending war on bacteria
Fungal pathogens are less well-known than bacteria, viruses and parasites, simply because they were once mostly annoying infections like nail infections and athlete’s foot.
But with medical advances, such as organ transplants or cancer chemotherapy, more people are being immunosuppressed, and life-threatening fungal infections have appeared. The newest addition to these infections is the fungal superbug Candida auris.
Resistant to drugs and hard to diagnose, Candida auris emerged seemingly out of the blue in 2009 on several continents, causing intensive care shutdowns and killing people.
Professor Traven says the mortality rate for a systemic Candida infection, while not easy to estimate due to patients suffering from additional diseases, is probably about 10-20%.
“We need to understand better why some people get sick and why some people just breeze through COVID or other infections. Because once we understand that, maybe then we can come up with new therapies.”
Because the field had been ignored in funding for a long time, there are very few drugs that can be used to treat these infections.
“In my lab we do some drug discovery work – trying to find compounds that would kill these resistant fungal species.
“But we also work on understanding how our immune system works to defeat these pathogens. We are trying to work out what we could do to sort of shift the balance during infection, towards a useful immune response that would help the patient.
“We think there's an opportunity there where you could try and manipulate the immune response, which is our body's way to fight the fungus. “
But it takes a long time to develop drugs and treatments, to understand the disease to develop diagnostic methods.
“We're talking decades, and even the vaccines now for COVID, if they're successful, the groundwork has been done over many, many years.
“I think this current pandemic will teach the public that we can have a vaccine within a year if we really want to, but that's really an exception to the rule.
“It is not something that you can do in five minutes.”
