The cases were among 716,997 test results submitted to the Illinois Department of Public Health.
The seven-day testing positivity rate is at 2.4 percent, health officials said.
State health officials said 76 percent of Illinois' total population have received at least one vaccine dose and more than 67 percent are fully vaccinated. Almost 49 percent have received the booster shot, health officials said.
Since the beginning of the pandemic, Illinois has recorded 3,026,737 cases and 32,654 deaths tied to COVID-19.
As of Thursday night, 1,143 Illinoisans were hospitalized with COVID-19, with 211 needing intensive care and 103 on ventilators.