As the United State passes the one million mark for documented cases of Covid-19, one of the most frustrating aspects of the current pandemic is that identification and extent of community outbreaks is tied to the number of test kits available. Due to inadequate test kit supplies, available testing has been limited to individuals already experiencing symptoms. This, in turn, has limited the number of identified cases to the number of kits. It is now suspected that in the California Bay Area, the virus may have been circulating in the population more than a month before health officials began looking for it (LA Times, April 11, 2020).

Finding a quick way to locate and identify disease outbreaks before they manifest in the community has researchers at several universities focusing their attention on a surprising yet familiar matrix—wastewater. Interest in the new field of wastewater-based epidemiology (WBE) has gained traction and offers a promising way to identify coronavirus using wastewater. “WBE holds the promise of near real-time monitoring of disease outbreaks,” according to an April 23, 2020 news release from Arizona State University.

Researchers at Stanford and the University of Michigan appear to agree. In a news release from U of M, Stanford Professor of Environmental Engineering, Alexandria Boehm, is quoted as saying, “Our hope is that we can detect an uptick in cases with this tool faster than we can through clinical testing. We don’t know that for sure but that’s the hypothesis.”

And there’s good reason Boehm and other scientists believe wastewater will prove effective, because it turns out that this is not the first time sewage has been used to understand and track viruses. Researchers helped characterize a polio outbreak in Israel in 2013 by developing a mathematical model to better interpret and predict the extent of the polio outbreak. Public health officials in Israel could then better respond and presumably target vaccination to best effect (The Conversation, October 19, 2018).

In the case of Covid-19, the absence of a vaccine makes early identification of community outbreak paramount if we wish to contain and eradicate it. If it is known that the virus is active before people exhibit symptoms, members of the community can be cautioned to practice social distancing and sensitive populations can be advised to self-isolate in advance of widespread exposure. This is critical if we wish to re-open businesses and public spaces in a safe and responsible manner. Wastewater testing may equip states with the data they need to identify and contain COVID-19 hotspots and flareups, while allowing non-detect communities to cautiously resume normal community operations.

This pandemic still poses many questions, but those of us in the environmental field are hopeful that wastewater holds some answers.