A groundbreaking study reveals that aircraft wastewater can detect antimicrobial-resistant superbugs, offering a novel, cost-effective method for global surveillance of antibiotic resistance
Researchers from the University of South Australia have discovered that aircraft toilets could play a key role in monitoring the spread of global superbugs. By analysing wastewater from planes, scientists can detect antimicrobial-resistant bacteria, providing a cost-effective and real-time method to track antibiotic resistance across countries and continents. This innovative approach could help public health authorities respond faster to emerging threats.
The findings are detailed in Microbiology Spectrum.
Superbugs were discovered on 44 different flights
A new study led by scientists from Australia’s national science agency CSIRO, in partnership with Xiamen University, the University of South Australia, and Michigan Technological University, analysed lavatory wastewater from 44 international flights arriving in Australia from nine countries. Of these 44 international flights, 18 originated from India, 14 from the UK, six from Germany, and the rest from France, the UAE, Türkiye, South Africa, Japan, and Indonesia.
The researchers found nine high-priority pathogens and superbugs, including some that are only acquired in hospitals or are resistant to multiple drugs. They used advanced molecular techniques to analyse the superbugs’ genetic signatures and antibiotic resistance genes (ARG) profiles.
The team found that five of the nine superbugs identified were discovered in all 44 flight samples, and a gene conferring resistance to last-resort antibiotics was detected on 17 flights. Strikingly, this specific gene was absent in Australia’s urban wastewater during the same period, suggesting its likely introduction through international travel. These findings confirm that aircraft wastewater is a viable tool for global AMR surveillance.
“Aircraft wastewater captures microbial signatures from passengers across different continents, offering a non-invasive, cost-effective way to monitor threats like AMR,” senior author Dr Warish Ahmed, a principal research scientist from CSIRO, commented.
The samples also indicated significant geographic variations according to co-author Professor Nicholas Ashbolt. “Flights from Asia, particularly India, showed higher concentrations of antibiotic resistance genes, compared to flights from Europe and the UK,” Prof Ashbolt said.
Dr Yawn Liu says that these disparities could reflect differences in antibiotic use, water and sanitation, population density and public health policies across regions. This suggests that targeted interventions, such as improved sanitation and antibiotic stewardship programs, could help reduce the spread of antibiotic resistance.
International travel is a major driver of AMR spread
The researchers also looked at whether disinfectants used in aircraft toilets degraded genetic material. They found that nucleic acids remained stable for up to 24 hours, even in the presence of strong disinfectants, confirming the reliability of aircraft wastewater for surveillance purposes. It is well documented that infectious diseases such as COVID-19 and influenza are spread by air travel.
“International travel is one of the major drivers of AMR spread,” says Dr Liu. “By monitoring aircraft wastewater, we can potentially detect and track antibiotic resistance genes before they become established in local environments.”
The genetic samples used in the study were collected during the COVID-19 pandemic repatriation flights, which may have influenced passenger demographics. The authors say that this approach can be adapted to routine international travel, though.
“With AMR projected to cause more than 39 million deaths globally by 2050, the need for innovative surveillance tools is urgent,” Prof Ashbolt said.
“Aircraft wastewater monitoring could complement existing public health systems, providing early warnings of emerging superbug threats.”
“This is a proof-of-concept with real-world potential,” added Dr Ahmed. “We now have the tools to turn aircraft toilets into an early-warning disease system to manage public health better.”