DuPage, DeKalb and Kendall counties have been raised to a 'high' risk level.
CHICAGO (WLS) -- Illinois reported 3,348 new COVID-19 cases and 22 new deaths Thursday.
COVID-19 transmission has been raised to a "medium" risk level in Cook County as well as many of its surrounding counties, according to the U.S. Centers for Disease Control and Prevention.
DeKalb, DuPage and Kendall counties have moved back into the "high" risk COVID community level.
There have been at least 3,966,544 total COVID cases in the state since the start of the pandemic and at least 35,750 related deaths.
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As of Wednesday night, 1,807 patients in Illinois were reported to be in the hospital with COVID-19. Of those, 218 patients were in the ICU, and 75 patients with COVID-19 were on ventilators.
The daily case rate per 100,000 population is 18.4.
Chicago Mayor Lori Lightfoot said Chicago could issue a mask advisory if Cook County reaches a high transmission level of COVID-19.
Mayor Lightfoot made the announcement at a press conference last Thursday.
"Not only will this protect you, but it will also protect those around you, including some of our most vulnerable older residents and those with compromised immune systems," Mayor Lightfoot said. Preventing the spread of COVID now will also protect our healthcare system from being overwhelmed with COVID-19 cases."
Just last week, Lightfoot announced she had tested positive for COVID-19.
She just exited a five-day quarantine after testing positive and says she was asymptomatic throughout it.
She followed Centers for Disease Control and Prevention guidelines and wore a mask throughout Thursday's news conference.
Booster rates remain very low, and health officials are urging people to get the shot before the holidays, as cases are on the rise.
Since the bivalent booster has been around since September, the CDC released a detailed report on how it's been working for the past few months. Data show the booster cuts hospitalizations and ER visits by at least 50%.
Chicago and Cook County are predicted to move into high risk soon, and Stroger Hospital is planning for a possible surge.
Besides the bivalent booster, some doctors said it's time to make home testing a regular routine again.