Rising levels of coronavirus in sewage can forewarn an outbreak before other metrics such as hospital admissions and case counts, according to a study published Friday.
That means sewage could be an effective way of tracking the virus, especially when coronavirus tests are in short supply, researchers said.
“Our study could have substantial policy implications,” wrote engineering professor Jordan Peccia and colleagues at Yale University. “Jurisdictions can use primary sludge [coronavirus] concentrations to preempt community outbreak dynamics or provide an additional basis for easing restrictions, especially when there are limitations in clinical testing.”
Coronavirus has been found in the stool of Covid-19 patients. In the study, which hasn’t yet been peer-reviewed, researchers compared levels of the virus in “primary sludge samples” to hospital and test data.
Testing sewage to track outbreaks has been done for other diseases. Places in the US are also considering testing wastewater.
Earlier this week, Honolulu said it plans to check 1,000 samples from its main sewage plant.
Mayor Kirk Caldwell said the testing would give officials an early indication of whether infections are on the rise. “It shows trend lines, and it alerts people — in our case, the city and county of Honolulu — whether we have a problem,” Caldwell said Tuesday.