People infected with SARS-CoV-2, the virus that causes COVID-19, are known to shed it in their stool, even if they aren’t experiencing any symptoms. With that in mind, University of California San Diego School of Medicine researchers have been screening wastewater from campus buildings for signs of the virus since the summer of 2020, thinking the information could help prevent outbreaks.
Now they have data to back it up: Screening for SARS-CoV-2 in wastewater, the team showed they can detect even a single infected, asymptomatic person living or working in a large building. Notification to occupants of each building with positive wastewater increased COVID-19 testing rates by as much as 13-fold. Once an occupant tested positive, isolation and contact tracing helped prevent further spread of the virus.
The approach enabled early detection of 85 percent of COVID-19 cases on the campus, researchers reported in the August 10, 2021 issue of mSystems. In other words, wastewater samples tested positive before most individual case diagnoses.
