LETTERS: Op-ed submission: Antimicrobial resistance and wastewater surveillance

Every day, beneath our cities, a silent early warning system operates. Wastewater flowing through sewers holds clues to antibiotic-resistant bacteria, or "superbugs," before outbreaks become evident in hospitals or communities. This proved its worth during the COVID-19 pandemic, but its potential for combating antimicrobial resistance remains underutilized.

Unlike viruses that spread rapidly and visibly, antibiotic resistance creeps quietly across hospitals, farms, and communities until treatments become ineffective. Infections that were once easily treatable can become increasingly difficult, sometimes impossible, to cure. Antimicrobial resistance already causes an estimated 1.3 million deaths annually. This is not a future crisis; it is a present one.

As an environmental microbiology researcher, I have witnessed these patterns emerge before they surface in clinical data. Wastewater reflects the collective biological footprint of entire populations, offering a real-time, population-level view of public health. This strength lies in its efficiency and ability to detect changes early.

Human activity leaves biological traces in sewer systems, including bacteria, viruses, chemical residues, and genetic material. Analyzing these samples enables researchers to monitor entire populations without testing individuals individually, making wastewater surveillance both efficient and valuable for early detection.

During the pandemic, countries leveraged wastewater data to track infection trends, identify variants, and guide decision-making, showcasing the value of this approach. However, applying it to antimicrobial resistance is more complex. Researchers must monitor a dynamic landscape of resistance genes, microbial communities, and environmental pressures, which evolve in response to antibiotic use, sanitation, urbanization, and ecological changes.

Despite advances in genomics and data analysis, the real challenge lies in implementation. Wastewater monitoring for antimicrobial resistance remains fragmented and often confined to short-term research projects. Data collection methods vary, hindering comparison, and the generated information is seldom integrated into public health decision-making consistently.

This missed opportunity exists as wastewater data could provide early warnings of emerging resistance trends, identify hotspots, and assess intervention impacts in near real-time. It can also capture signals from underrepresented populations in clinical surveillance. To address antimicrobial resistance as a global threat, our surveillance systems must be equally comprehensive.

A shift from isolated research efforts to integrated public health strategies is necessary. This requires investment in standardized methods, improved data sharing, and stronger collaboration among scientists, policymakers, and infrastructure providers. It also demands recognizing that environmental data are not separate from health systems but essential for understanding resistance spread.

Early signs of progress are emerging, with some initiatives aligning wastewater monitoring with existing surveillance frameworks. However, without sustained commitment, these efforts will remain limited in scale and impact. Antimicrobial resistance is often referred to as a silent pandemic due to its invisibility until it is too late. The danger lies in its lack of visibility until it becomes unmanageable. The question is whether we are willing to act on the warning signs already flowing beneath our cities daily.