Wastewater provides early detection of COVID-19 variant transmission

Editor's Note

Scientists at UC San Diego and Scripps Research have developed tools to analyze wastewater that have proven effective in identifying emerging COVID-19 variants and predicting surges.

COVID-19 patients shed the virus in their stool, whether they have symptoms or not. In the summer of 2020 the scientists began robotic sampling of wastewater on the UC San Diego campus, and currently almost 350 buildings on campus are being monitored.

The program has been a success, allowing students to return to campus in mid-2020. In March 2021, wastewater surveillance went regional, with multiple samples sequenced each week from San Diego County’s primary wastewater treatment plant.

The scientists can now accurately determine the genetic mixture of COVID-19 variants in just 2 tsp of raw sewage and identify new variants of concern up to 14 days before traditional clinical testing. They detected the Omicron variant in wastewater 11 days before it was first reported clinically in San Diego.