New research from the School of Medicine and the School of Engineering offers some of the first clear guidance on the most effective methods to test wastewater for COVID-19. Such testing can identify new cases – even asymptomatic ones – and help prevent spread in congregate living settings such as nursing homes, dormitories and barracks.
The research draws on real-world experiences right here at UVA. Our Amy Mathers, MD, collaborated with UVA Engineering's Lisa Colosi-Peterson, PhD, and colleagues to monitor wastewater from two student dormitory complexes for eight weeks.
UVA required students to undergo periodic COVID-19 testing to help prevent the spread of the disease, so the researchers were able to compare the wastewater testing results with the known numbers of positive cases in the buildings. They found that the wastewater testing caught more than 96% of cases.
The project allowed them to evaluate sampling and analysis techniques to identify best practices for wastewater testing. For example, the testing proved highly useful for detecting initial infections, but less so for determining the number of building residents infected or how long they had been infected.
One important finding: Wastewater testing can detect even small numbers of asymptomatic cases. That hadn't been previously documented, and is important information for controlling COVID's spread.
“This work could be applied to surveillance in buildings where people live in groups, where transmission may be hard to control but the risk of spread could be high,” Dr. Mathers said. “Since we can identify new infections with high sensitivity, it provides an early warning signal of when to test everyone in the building to find and isolate the newly infected persons before an outbreak becomes large.”
Dr. Mathers and co. detailed their full findings in Applied and Environmental Microbiology.