Data from wastewater treatment centers helps track rapid spread of COVID-19

JANESVILLE, Wis. — Current and recent data suggests there are more people currently infected with COVID-19 than the number of confirmed PCR tests that have been reported, according to Rock County’s health department and the city of Janesville.

Tracking the number of people with COVID-19 often relies on the conventional testing of people who are showing symptoms of infection or who have had close contact with a person who has tested positive. That, however, doesn’t capture the full extent of the virus’ presence in the community, officials said.

The use of wastewater monitoring helps gather a more comprehensive understanding of the virus’ spread in the community.

“With the advent of having the home tests, there are plenty of people I’m sure who are testing positive for COVID that, if their symptoms aren’t bad enough to go to the hospital, they’re hopefully self-quarantining,” Brian Skaife from Rock County Wastewater said. “Those are numbers we’re maybe not seeing, but the wastewater doesn’t lie.”

In a news release, Nick Zupan, an epidemiologist with the Rock County Public Health Department, said wastewater data shows “much higher levels (of COVID-19) now than any other time in the pandemic.

The city of Janesville has taken part in a wastewater monitoring program since September 2020. Dozens of wastewater districts across the state, including the Madison Metropolitan Sewerage District and facilities in Sun Prairie, Portage, Platteville, also participate.

In south-central Wisconsin, the latest wastewater data shows a sustained increase in COVID-19 levels in Columbus, Lake Geneva and Lodi.

To view the latest data from each facility, click here.