Wastewater: a Diagnostic Tool for Community Health

Wastewater surveillance has long been explored as an early warning system — a way for communities to spot brewing health threats before hospitals fill up. During the COVID-19 pandemic, it proved a game-changer, often detecting viral surges 4–10 days ahead of rising admissions.

Today, public health agencies are broadening the use of wastewater to track influenza, RSV, norovirus, antimicrobial resistance genes, and other diseases. Recent studies show wastewater levels of influenza A and RSV closely mirror ER visits, while near-source monitoring is picking up multiple pathogens — from norovirus to flu — across community sites.

Wastewater Surveillance System: How does It Work (Credit: CDC)

Extreme weather, however, is complicating this frontline defense:

• Heavier rainfall & flash floods overwhelm sewers, pushing pathogens into rivers and muddying trend signals.

• Heat waves & droughts shrink water volumes, concentrating pollutants and stressing treatment systems.

• Extreme events disrupt sampling, precisely when early warnings are most critical.

  
  

A WHO analysis underscores that climate change is heightening the risks of waterborne disease outbreaks, making robust wastewater monitoring a critical pillar of health adaptation. If we want truly climate-resilient health systems, we can’t stop at hospitals and flood barriers. We need smart, scalable early-warning networks. While it comes with constraints, wastewater remains one of the most valuable tools we have.

Impacts of Climate Change on Public Health (Credit: World Health Organization)

[First published on Substack "Ginci Insights" on July 16, 2025: https://gincinno.substack.com/p/wastewater-a-diagnostic-tool-for?r=2cxt8s]