Mainstreaming Wastewater Surveillance for Infectious Disease
- During the Covid-19 pandemic, valuable intelligence on trends in the infection rates, variants, and distribution of SARS-CoV-2 in the United States was obtained from the humblest of assets: the country’s sewage.
COVID Pandemic
The Covid-19 pandemic has brought about a new approach to understanding disease dynamics and trends in infection rates, variants, and distribution of SARS-CoV-2 in the United States. Organizations have been using wastewater to gain insights into the spread of the virus. The Centers for Disease Control and Prevention (CDC) has asked the National Academies of Sciences, Engineering, and Medicine (NASEM) to assess the value of community-level wastewater surveillance in controlling infectious diseases beyond Covid-19. The committee’s report described its vision for transitioning to a truly representative, sustainable, national wastewater surveillance system.
Challenges in Surveillance
Wastewater surveillance for infectious disease has been around for some time, but it expanded during the pandemic after intense work and the establishment of new partnerships among public health departments, the CDC, municipal utilities, private analytics companies, and academic institutions. However, there are challenges in achieving a representative, sustainable, national wastewater surveillance system. The first challenge is ensuring equity, as sites are unevenly distributed, and one in six Americans live in unsewered locations. The second challenge is ensuring timeliness, as acceptable lag times will vary with the specific threat.
Problem- Solving
To achieve this goal, staff at community wastewater treatment plants must be integrated into the public health system. Wastewater sampling is typically performed by water utility staff, but collaborative relationships between water utilities and health departments are not yet widespread. Wastewater data must be timely and integrated with other data, such as clinical encounters and testing, to be actionable. Integrating diverse data streams into a common, accessible portal will provide the most robust information. The CDC can work towards creating an integrated, plug-and-play data portal through its agency review process and Data Modernization Initiative.
Potentials for Future
There are disparities in analytic capacity among localities, and current methods for processing, detecting, and quantifying pathogen biomarkers in wastewater have limited ability to be multiplexed and vary in performance efficiency across targets. The CDC could apply three criteria to evaluate potential targets: a pathogen’s public health significance, the analytic feasibility of monitoring the target in wastewater, and the usefulness of wastewater data in informing public health action. Wastewater information is most useful when it adds substantially to what can be learned from alternative surveillance sources. Promising targets for wastewater surveillance beyond SARS-CoV-2 include influenza viruses, enterovirus D68, and emergent antimicrobial-resistance genes. Wastewater surveillance stands out as a bright spot in the Covid-19 pandemic, but a permanent national surveillance system requires additional and new kinds of federal investments.