The recent surge in the Delta variant of the virus that causes COVID-19 has forced many to reconsider their idea of how and when this pandemic will end and what communities will need to help bring it to a close. In this article for The Atlantic, staff science writer Ed Yong examines the new landscape of the pandemic and how we can shift our expectations from eradicating the virus toward suppressing its spread and tracking its presence as it lingers in our societies.
“What we need,” Yong quotes infectious disease expert Samuel Scarpino of the Rockefeller Foundation as saying, “is a nimble, comprehensive system that might include regular testing, wastewater monitoring, genetic sequencing, Google-search analyses, and more.” The future of the COVID-19 pandemic response, in other words, is going to require reliable systems for determining where the virus is, what variant of the virus is infecting people, and quickly communicating this information so individuals and communities can take action.
Healthy Davis Together is proud of the work we’ve done to put systems in place that can provide actionable data for years to come. Of central importance is our wastewater monitoring program, which allows us to detect levels of the virus that causes COVID-19 (SARS-CoV-2) in normal sewage passed through the excrement (feces) of individuals who are infected, including asymptomatic and pre-symptomatic individuals. The program can detect levels at both city and neighborhood scales and includes a communications protocol that turns that data into action.
In Davis, wastewater monitoring supplements clinical testing so that even when testing rates are low, as they were this summer before the recent surge, city and public health officials can see whether the presence of the virus is increasing or decreasing and locate areas with potential hotspots. This allows us to identify and anticipate where a surge in cases may occur based on spikes in the data, and quickly target communications and testing directly to those areas.
Here’s how it works:
- Wastewater samples are collected three times a week from more than a dozen locations across the sewer system as well as from the municipal water treatment plant for the city.
- The samples are taken to a lab and analyzed, and the data is reported to a wastewater working group of city and public health experts.
- On Fridays, time is set aside for this working group to discuss recent results and determine if any action needs to be taken. If the data show a sustained increase in the prevalence of COVID-19 over preceding sampling periods, messages and materials are shared with the neighborhoods where there may be an increased spread.
- Every Saturday, wastewater monitoring results are published at the Healthy Davis Together website so that residents can see how Davis and their own neighborhood are doing.
This process and data are important in guiding our public health response. When we detect sustained increases over a week or two, our communications response can include press releases, alerts via email, text, and phone calls, fliers, and door hangers delivered directly to residences in the affected areas with information and guidance on how to get tested and practice COVID safety, including social distancing, thoroughly washing hands and surfaces, and wearing masks.
For example, in July of this year, Healthy Davis Together responded to spikes in three different neighborhoods, delivering 3,000 door hangers and sending text notifications to 4,000 individuals. For residents in apartment complexes that we weren’t able to reach directly, we contacted the owners of the complex to encourage them to forward information to their residents about the Delta variant and the recent wastewater data.
While wastewater monitoring isn’t new, it’s unfamiliar to many in the community, so we’ve also been taking action to communicate about what it is and why we’re doing it. With a page of our website dedicated to explaining the importance of this monitoring, as well as video and written informational materials on the value of testing wastewater, we’re giving the community a look into the science and the people behind the effort.
We’ve also developed and are committed to sharing resources like our Wastewater Monitoring Playbook through press releases, media, journal articles, and conferences so that other cities and communities can quickly and easily implement their own environmental monitoring programs.
Healthy Davis Together is not alone in using wastewater monitoring to inform our pandemic response. We are excited to be exploring opportunities to expand these efforts outside Davis in partnership with communities in Yolo County, and we’re proud to be part of the Sewer Coronavirus Alert Network (SCAN) operated out of Stanford University, which unites wastewater monitoring programs from across California.
We hope that renewed discussions of the value of long term coronavirus tracking systems like wastewater monitoring, including Ed Yong’s article in The Atlantic, will help drive investments in this critical infrastructure and help even more communities include this tool in their pandemic response. As Mr. Yong points out, these programs can serve as critical infrastructure for years to come, helping to guard against a resurgence of COVID-19 as well as potential future threats to public health. While the end of the pandemic may look different now, there is a great amount of hope provided by these efforts to promote awareness, safeguard health, and foster readiness for the future.