Can Wastewater Surveillance Be Effective Without Modern Sewer Systems?

Wastewater monitoring has become a vital tool in understanding public health, especially evident during the COVID-19 pandemic when it enabled early detection of outbreaks across communities. In countries like the United States, extensive sewer networks collect fragments of feces, urine, skin cells, sweat, and blood, providing a community-wide health snapshot without invasive testing. This approach proved indispensable in tracking virus spread, including influenza and RSV, by analyzing small samples from large-scale sewage systems.

However, such sewer infrastructure is not universally available. Globally, over 3.5 billion people lack access to safely managed sanitation, with waste often disposed into open drains or pits. This gap limits the application of traditional wastewater testing, leaving many populations unmonitored.

To address this disparity, a collaborative team from Tufts University and international partners conducted a groundbreaking study to assess whether wastewater surveillance could be adapted for use in areas lacking modern plumbing. The study focused on two high-risk sites in Côte d'Ivoire: open wastewater channels in densely populated neighborhoods and water used for poultry cleaning at markets. Over 12 weeks, researchers collected and tested samples for SARS-CoV-2, the virus responsible for COVID-19, and influenza A, associated with bird flu.

Their findings were promising. Nearly 50% of sampled wastewater streams carried signs of COVID-19, and flu viruses were detected in poultry wastewater. Importantly, these results demonstrated that wastewater monitoring could be effectively implemented in resource-limited settings without relying on sophisticated infrastructure. The team also trained local scientists to conduct testing, showing that this approach can be low-cost and sustainable.

This innovative work underscores the importance of expanding wastewater surveillance to underserved regions worldwide. Infectious diseases do not respect borders; early detection in low-resource settings can help prevent global spread. For instance, monitoring for viruses like Ebola or Lassa fever—diseases that often go unnoticed due to limited testing—becomes possible through these adaptable methods.

Looking ahead, efforts must continue to refine low-cost sampling and testing techniques, enabling broader use of wastewater surveillance in diverse environments. Feasibility in rural or informal settlements offers a new pathway for global health monitoring, especially as diseases transmit silently and often threaten to escalate into outbreaks.

In summary, adapting wastewater surveillance in areas without modern sewer systems is a vital step toward equitable health monitoring worldwide. It holds the promise of early detection and containment of infectious diseases, ultimately contributing to better global health security.

Source: https://medicalxpress.com/news/2025-08-qa-wastewater-surveillance-sewers.html