Loss of federal funding has led to COVID-19 testing site closures throughout Illinois, and the nation. Milder symptoms for those who are vaccinated and increased use of at-home rapid tests, which people rarely report to health authorities, means accurate COVID-19 data is increasingly hard to come by. 

Fewer than half of Illinois’ 102 counties are participating in a statewide program that monitors the virus that causes COVID-19 and its variants in wastewater. But state health officials say the participating 68 wastewater treatment plants in 48 counties covers more than 80% of Illinois’ population.

A University of Illinois Chicago lab and its partners have been tracking the virus that causes coronavirus in wastewater and sharing the data with local public health agencies.