Insights from Auckland sewers could help fight superbugs
Scientists are turning to Auckland’s sewer network to get a better handle on antibiotic resistance — a fascinating approach that’s also been used to flush out illegal drug use and now coronavirus.
Learning more about superbugs’ ability to defy remedial drugs is critical: An estimated 700,000-plus people worldwide die each year due to drug-resistant infections and that could climb to 10 million by midcentury.
The new study’s leader, University of Auckland microbiologist Associate Professor Siouxsie Wiles, said New Zealand monitored antibioticresistant bacteria by analysing samples collected from hospital and community laboratories.
Although this is a tried and true system, its main flaw is it fails to capture information on resistant bacteria carried by healthy people with no symptoms. “So far studies looking at antibiotic resistance use samples taken from people who have been to the doctor or hospital,” she said. “We don’t have a clear idea of what superbugs are out there in the general public.”
Wiles said healthy people could harbour some of these superbugs in their nose or gut without any woes.
“However, one day they might end up needing surgery and perhaps that organism will end up in their bloodstream where it will become very difficult to treat.
“Or they could inadvertently pass it on to someone else,” she said.
Her two-year study, supported with a $150,000 grant from the Health Research Council (HRC), would sample hospital effluent and compare it with samples from wastewater treatment plants serving “healthy” communities without a primary-care facility in the catchment area.
Various testing methods would be used to see which got the best result.
That included trying to identify the antibiotic-resistant bacteria, looking for their genetic material — similar to the test for Covid-19 — or sequencing all material in the sample to see what was present.
It’s possible researchers will end up with an archive of samples that can be analysed for all sorts of pathogens, not just antibioticresistant bacteria.
While the data gathered would not be able to pinpoint individuals carrying antibiotic-resistant bacteria and resistance genes, it could be used to model and map outbreaks at a neighbourhood level, something Wiles is wary of. “One of the key things we want to determine through this study is at what scale is it appropriate to go down to.
“Just because we have the technology to model the level of antibioticresistant genes down to a neighbourhood level, it does not necessarily mean that we should,” she said. “We are acutely aware of the need to carry out this work safely and ethically so that it doesn’t stigmatise communities or perpetuate inequalities.”
HRC chief executive Sunny Collings said the information gained from this study could give clinicians advance notice of which antibiotics would work on their patients, saving vital time — and possibly lives.
It could also help public health officials make better-informed decisions on where infection-control policies would best be applied — policies crucial for preventing infections in vulnerable patients as well as those having routine surgeries such as knee or hip replacements.
“The World Health Organisation has called for drastic action to avert a return to the pre-antibiotic era.
“It’s becoming more and more difficult and expensive to treat people who have antibiotic-resistance, and while we aren’t yet seeing widespread deaths globally like we’re currently experiencing with the Covid19 pandemic, it will happen at some point if we don’t tackle it head on.”
Her study is one of 17 Explorer Grants, worth a combined $2.55 million.