Follow the feces. Wastewater data is one of our best remaining tools for COVID-19 surveillance.
With the end of the COVID-19 public health emergency in the US, the US CDC will stop reporting community levels of COVID-19 cases or positivity rates. The accuracy of these numbers has also likely declined over time as people tested more at home or stopped testing altogether.
The CDC will continue to track COVID-19 hospitalizations, ICU admissions, and deaths. But as we know, these are often lagging indicators that increase only weeks after a surge in cases, so they don’t help people take action to protect themselves.
If you want to continue to monitor COVID-19 dynamics and adjust your precautions as needed, follow the feces .
People infected with SARS-CoV-2 shed the virus in their stool whether or not they have symptoms and whether or not they seek testing. This makes untreated sewage a good source of tracking the ups and downs of the virus across time and geography. When case counts were carefully tracked, wastewater and official metrics consistently moved together, giving us more confidence that wastewater is a good proxy for infections.
Wastewater surveillance for SARS-CoV-2 began in 2020 and currently covers over 1400 sites across 50 states, or around 40% of the US population. More local areas are adding this capacity over time, so this coverage should only get better.
While we data nerds wish we had better surveillance of individual-level COVID-19 cases over time, we are happy to see the expansion of this tool and hope it is expanded to monitor other infectious diseases. Wastewater is not perfect, but it can serve as an early warning sign as new waves of infection and new variants emerge.
Despite the end of the public health emergency, COVID-19 is still with us. It’s still more dangerous than the flu, with over 1000 deaths a week in the US.
Check your local and regional data here:
Stay safe, stay well.
Those Nerdy Girls
“As Covid Emergency Ends, Surveillance Shifts to the Sewers”