Chicago collecting sewage samples to track surges in COVID-19 cases

CHICAGO (WLS) -- Testing may not tell the real story on how widespread or limited COVID-19 may be in certain neighborhoods. The truth may come from wastewater.

A growing number of communities in the United States are collecting sewage samples as a way to track surges in coronavirus cases.

Chicago is scrambling to use this type of testing in an effort to give hospitals more time to prepare for outbreaks in some neighborhoods.

Not everyone gets tested and not everybody who gets infected with COVID-19 shows symptoms.

"Even though we think of it as a respiratory infection which it certainly is, the virus remains in stool even after somebody has gotten over their symptoms," said Sam Dorevitch, UIC School of Public Health researcher.

According to Dorevich, there are high levels of COVID-19 in stool. To track the virus, UIC is in the process of studying sewage samples from the city's water treatment plants.

"We are doing this project really to help the Chicago Department of Public Health get a good sense of where the disease is where it's highest where it's lowest where it's changing," said Dorevich.

Tracking it can give hospitals more time to prepare for outbreaks. While the project begins with the treatment plants, the study will become large scale when it collects samples from different Chicago neighborhoods.

Testing will begin in the neighborhoods before the end of the year and will really ramp up in January.

Neighborhood testing will involve opening up manhole covers while the project aims to help the city track the virus, researchers have other goals as well.

"The other goal is more longterm to set up a network of wastewater monitoring so that when the next pandemic arrives, we'll have a head start," said Dorevich.

Researchers said testing wastewater is much more efficient and possibly a more accurate way to track diseases than completely relying on people getting tested.