A public health response is needed because environmental reservoirs promote drug-resistant infections

A public health response is needed because environmental reservoirs promote drug-resistant infections

Resistance to antimicrobials in the environment is turning rivers, soils and even the air into hidden transport routes for “superbugs,” says a new study that calls for urgent, coordinated action for human, animal and environmental health. The authors argue that protecting people from drug-resistant infections now depends as much on wastewater plants and farms as it does on hospitals.

A growing ecological “superbug” crisis

Antibiotic resistance (AMR) arises when bacteria and other microbes develop the ability to survive drugs that once killed them, making it difficult or impossible to treat common infections. The World Health Organization already lists AMR as one of the most serious global health threats of this century. Some estimates warn of tens of millions of deaths and massive economic losses if measures fail.​

The new study shows that the environment is not just a passive backdrop. Rivers, lakes, soils, oceans and even the air can carry resistance genes and resistant bacteria that move between wildlife, livestock and people, helping to create a truly global network of AMR.​

Important springs and hidden reservoirs

The review highlights several major environmental “hotspots” where resistance is building and spreading.​

• Hospital and city wastewater treatment plants act as central mixing centers, collecting antibiotic residues, resistant pathogens and mobile genetic elements from households and clinics. Conventional treatment often fails to completely remove these pollutants, so that resistance genes remain in the wastewater and sewage sludge.​

• Livestock farms and aquaculture systems use large amounts of antibiotics and accumulate resistance genes in animal gut microbes and manure, which then leach into soil, crops and surrounding waters.​

• Pharmaceutical production facilities can emit extremely high levels of antibiotics and resistance genes, increasing the risk that dangerous resistance traits will spread further.​

Across these sites, resistance genes can hitchhike to mobile genetic elements such as plasmids, making it easier for bacteria to “swap” resistance traits and create multidrug-resistant strains.​

Why traditional surveillance is not enough

The majority of AMR monitoring still focuses on clinical samples, but the authors argue that there is some catching up to do in environmental monitoring. Classic culture-based tests remain important because they measure whether bacteria actually survive antibiotics and provide live isolates for further study. However, many environmental bacteria cannot be easily grown in the laboratory, and these methods can miss most existing resistance.​

Newer tools are changing the picture rapidly:

• Phenotypic methods such as flow cytometry and Raman spectroscopy can track resistant cells and gene transfer in complex samples within hours without the need for cultivation.​

• Genotypic methods such as high-throughput quantitative PCR, CRISPR-based assays, and metagenomic sequencing can detect hundreds of resistance genes simultaneously and identify which bacteria carry them.​

• Using long-read sequencing, researchers can now reconstruct entire mobile genetic elements and see exactly how resistance genes are organized and move between hosts.​

The message is clear. No single method can capture the entire history of environmental resilience. What we need is integrated surveillance that links what bacteria can do, what genes they carry and where they spread.”​

Huilin Zhang, lead author

One health and smarter damage control

The review is embedded in the One Health concept, which emphasizes that human, animal and environmental health are closely linked. The authors propose addressing AMR on two fronts: source control to reduce the amount of antibiotics, resistant bacteria and resistance genes entering the environment, and process control to intercept them along key pathways such as wastewater treatment.​

Source control measures include stricter use of antibiotics in medicine and agriculture, better regulation in low- and middle-income regions, and cleaner production in the pharmaceutical industry. The authors also highlight new “green” solutions, such as improved biodegradation of antibiotics, development of more biodegradable drugs, and alternative antimicrobials such as peptides and phages.​

On the process side, improved wastewater treatment and waste management are crucial. Conventional disinfection can reduce many resistant bacteria, but may result in resistance genes remaining intact, particularly in solid waste streams. More advanced approaches such as hyperthermophilic composting, advanced oxidation, membrane processes, nanomaterials, bacteriophage-based treatments, genetically engineered DNA-capturing bacteria and CRISPR-based tools are promising but require further research, safety assessment and cost reduction.​

Focus on the riskiest resistance

Rather than simply counting how many resistance genes are present, the authors argue that surveillance and policy should prioritize traits that actually increase health risk. Three stand out:​

• Mobility: How easily do genes move between bacteria and environments?

• Host pathogenicity: whether the bacterial hosts are capable of causing disease in humans or animals.​

• Multi-resistance: Whether genes and their hosts resist several important antibiotics, limiting treatment options.​

“Environmental antibiotic resistance is not just about how many resistance genes we can find,” said corresponding author Feng Ju. "What matters most is which genes are mobile, which pathogens carry them, and how they evolve in real ecosystems. This is where surveillance needs to focus and where containment will have the greatest impact."​

The authors call for global, standardized protocols that make environmental AMR data comparable across countries and over time. Without such standards, they warn, the world will struggle to identify emerging threats early enough and develop effective One Health measures that protect both people and the planet.​

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