Superbugs, or antibiotic-resistant bacteria, are one of the most pressing medical issues of this decade. Already some bacteria are completely immune to every single antibiotic we have, while others have become resistant to many.
This affects everyone, whether you are going into hospital for a routine surgery, or get a small infection from a rose thorn - without antibiotics, these easily treated issues can be deadly, like they often were before the discovery of penicillin.
Decades of over-prescription and misguided use of antibiotics have allowed antibiotic resistance to flourish, and the resistant genes keep passing onto other bacteria, and even other species.
But there is still hope. Many Australian researchers are focused on discovering new ways to tackle superbugs - by finding new antibiotics, looking at how we can pair together old ones, or discovering how we can kill bacteria without using drugs at all.
Looking for new antibiotics
Dr Alysha Elliott is looking for new antibiotic compounds in places we haven’t even thought to look yet. Chemists can send their compounds to the Community for Open Antimicrobial Drug Discovery (CO-ADD) at the University of Queensland, and Elliott and her team screen them to look for antibiotic properties.
“We’re encouraging chemists and researchers from all over the world to send in their chemistry to us and we’ll screen their compounds for free, hoping to find new diverse chemistry,” she tells SBS Science. “We have over 90 collaborators across 30 countries participating, and have screened over 40,000 compounds in the last 12 months.”
The team have plenty of interesting data so far, but their search is far from over.
“Most of the new drugs coming out on the market… are actually old antibiotics. This means that drug resistance is appearing a lot quicker than it used to,” explains Elliott.
“We are looking for novel chemistry that hasn’t yet been seen in microbes and therefore hopefully we can find something that is a little more susceptible in the future.”
Combining the old and the new
Jana Soares is a postgraduate scholar from the US, currently doing research at the ithree institute at the University of Technology Sydney. She is investigating whether pairing antibiotics can make them more effective.
“My project is to see if we can make antibiotics that don’t work well against P. aeruginosa more effective by pairing them,” says Soares. “When P. aeruginosa is treated with a certain class of antibiotic that it is not killed by, it becomes much more susceptible to another class of antibiotic that it is normally completely resistant to.”
This kind of research allows scientists to continue using older antibiotics (that currently don’t work), while they continue the search for more. But there are still some hurdles to get through.
“In order to show if this would be a viable treatment, we need to show if it works inside a host organism- not just a test tube… We are using a small 1 mm long, soil dwelling worm called C. elegans as our model for infection.”
This approach could be used on other types of bacteria in the future, and because the antibiotics are already in use, it means we can use it on difficult-to-treat infections ASAP.
From honey to tea tree oil
Dr Christine Carson is focused on finding alternatives to antibiotics, and ways we can fight superbugs without resistance.
“There are lots of natural products that could be useful alternatives to antibiotics to treat bacterial infections - tea tree oil, mannose derivatives, vinegar, weak acids to name just a few,” she explains. “For example, there are several studies showing that bacteria are unable to become resistant to tea tree oil.”
Unfortunately, small-scale studies mean they haven’t been effectively brought to the clinic, and are not being used by most doctors. Carson is adding to the body of research, but there is a long way to go.
“For many natural products such as honey or vinegar, there is no protectable intellectual property and they are essentially unpatentable. Without a patent, there is no commercial incentive for the research to be done,” Carson explains. “Many potentially useful, low-cost treatments simply will not get properly investigated for lack of funds.”
But don’t go slathering honey or vinegar on yourself just yet.
“Honey is not potent enough to take orally to fight systemic infection so its benefits are restricted to topical applications. Unfortunately, it’s not going to be a panacea for all ills.”