Air sampling in Dane County schools is helping health officials track flu and COVID-19, similar to how wastewater is increasingly monitored around the country for the coronavirus to gauge activity as fewer people get tested for COVID-19.

Since the beginning of the school year, flu and COVID-19 data from 16 air monitors at 15 schools in or near the county has been reported on Public Health Madison and Dane County’s respiratory illness dashboard. The devices, roughly the size of microwave ovens, are placed in communal spaces such as cafeterias. They suck air, including airborne viruses, into spongy material that is analyzed for viral genetic material.

“It can tell us about the virus without us needing to stick anything up anyone’s noses or even know who was in a space,” said Dave O’Connor, a UW-Madison researcher involved in the surveillance. “Air sampling should be something that lots of schools bring on board to understand what the respiratory virus transmission risk is.”

Monitors have been at seven schools in the Oregon School District for two years, where air sampling last school year tracked flu and COVID-19 activity as reliably as student absences, rapid tests at school and regular tests from samples collected at home, UW-Madison researchers recently reported.