Human waste may be the “canary in the COVID-19 coal mine,” according to new research.
Testing wastewater for the genetic signature of the coronavirus could give communities a way to spot surges in COVID-19 cases that would be faster than relying on the faltering COVID-19 testing system.
“The stakes are enormous,” writes Sharon Begley in STAT. “As states ease social distancing, they need to know if they are reopening too quickly. If they can’t detect a surge of cases until patients show up in emergency rooms, it could be too late to prevent a repeat of this spring, when hospitals in New York City and elsewhere were overwhelmed.”
“Wastewater epidemiology” has been used for decades to detect polio and, more recently, to estimate the prevalence of opioid abuse in U.S. communities, writes Begley.
Water utilities from Virginia and Oregon to Finland and Germany are already analyzing their own wastewater to detect the coronavirus’ genetic signature. The Water Research Foundation is identifying labs around the country that will soon participate in a quality control test by analyzing the same wastewater samples and then comparing their results.
In addition to detecting cases sooner, wastewater analysis can help communities get around the limitations of the swab tests used to detect COVID-19, including the fact that testing in the U.S. “is still nowhere near enough to test everyone every few days, which would be necessary to … safely re-open schools and workplaces,” writes Begley.
While wastewater testing is promising, scientists still have to figure out:
- When during the course of infection people shed virus in stool.
- Whether the amount of viral shedding is the same in severe, mild, and asymptomatic cases.
- Whether the quality of an area’s water affects the detection of viral genes.
- The best place in a water treatment facility to sample for the coronavirus.