Though the COVID-19 omicron variant is accounting for 73% of new infections in the U.S. as of this week, Chicago's top doctor said the percentage is likely even higher in the Midwest.
According to Chicago Department of Public Health Commissioner Dr. Allison Arwady, the majority of cases in the city are the omicron strain as of Tuesday, which is a jump from the 1% detected at the start of December.
"We tested about 300 specimens just in the new Chicago testing program and two of them were omicron, less than 1% -- that's as recent as Dec. 6. Two weeks later, the estimate you see in purple there, just about everything is now omicron," Arwady said of a graph of the omicron variant in the city shown during a press conference Tuesday.
In Illinois, the number of omicron cases increased from 17 reported Monday to 71 as of Wednesday, according to data from the Illinois Department of Public Health.
The state also reported 16,581 new cases of the virus in the last day, the most it has recorded in a single day in 2021, IDPH data showed. In fact, the number is the most in a single day since Nov. 5, 2020, when 17,608 new cases were reported.
At the same time, the state is also seeing a surge in newly-hospitalized coronavirus patients, with more residents seeking emergency medical care than at any point so far this year.
The state's first case of the variant was reported in a fully vaccinated Chicago resident on Dec. 7. On Tuesday, the Cook County Department of Public Health announced the variant was identified in a case in suburban Cook County.
Just days later, health officials there issued new mitigation recommendations, warning "suspected cases of the omicron variant are rising... and are likely to escalate quickly."
On Tuesday, Chicago Mayor Lori Lightfoot announced that anyone age 5 and older will be required to show proof of full vaccination to dine inside or visit gyms or entertainment venues where food and drinks are being served starting Jan. 3, joining other big cities like New York and Los Angeles in adding the requirement.
The city said the policy is "in response to an alarming rise in COVID cases both locally and nationally, driven in part by the omicron variant."
"Despite our diligent and equitable vaccine distribution efforts throughout this year,
unfortunately, our city continues to see a surge of COVID-19 Delta and now Omicron cases," Lightfoot said in a statement. "New steps must be taken to protect the health and wellbeing of our residents. This public health order requiring proof of vaccination to visit certain indoor public places is a necessary measure to ensure we can continue to enjoy our city's many amenities as we enter the new year."
According to the new guidelines, those 5 and older must show proof of full vaccination, but anyone ages 16 and older will also need to provide identification that matches their vaccination record. Employees at such venues will also need to either be vaccinated or wear a mask and show proof of weekly negative COVID-19 tests.
Addressing omicron concerns earlier this month, Dr. Ngozi Ezike, the director of the Illinois Department of Public Health, said while "we don't have all the answers right now," general prevention strategies such as masking, vaccination and boosters remain the best protection against the variant.
"As long as the virus continues to circulate, it has the potential to mutate into new variants," she said. "Vaccination can help stop circulation, but we need more people to get vaccinated.”