Mask requirements have been lifted in dozens of states and communities across the country, but that has yet to be the case in Illinois - one of six states where masks must still be worn in public indoor spaces.
Of the states where mask mandates remain in effect - Hawaii, Illinois, Nevada, New Mexico, Oregon and Washington - Illinois is the only one east of the Mississippi River.
An analysis of Centers for Disease Control and Prevention data showed that of the five aforementioned states excluding Washington, which didn't have data listed, Illinois had the second lowest positivity rate - between 3 and 4.9%.
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The positivity rate in Hawaii was less than 3%, making it the lowest out of the five states.
Illinois reinstated its mask mandate in late August, with Gov. J.B. Pritzker at the time saying the state was "running out of time as our hospitals run out of beds."
Toward the end of the month, Illinois saw a statewide positivity rate of around 5.7%, and all of its 102 counties were experiencing "high” levels of community transmission.
The positivity rate dropped as low as two percent in late September and stayed there until Nov. 16, when it rose slightly to three percent, according to the John Hopkins Coronavirus Resource Center.
Even as COVID cases have increased in recent weeks, some Illinois leaders, including the mayor of Naperville, have pushed for the removal of the mask mandate, noting no other Midwest states have requirements on the books.
A vast majority of Illinois' 102 counties are currently under a "high risk" category in which the CDC recommends residents wear masks regardless of vaccination status.
Defending the mask mandate, Dr. Jennifer Seo, chief medical officer with the Chicago Department of Public Health, said the U.S. is seeing higher numbers of cases in areas where the weather is colder.
Michigan and Minnesota, which don't have mask mandates, have the highest rates of COVID-19, the doctor noted.
"I think context matters in terms of where geographically the states are, and we know for sure that the colder weather," Seo said during a press conference Monday. "We're seeing that in Europe as well. The colder countries are seeing higher numbers of cases, so just something to keep in mind. But I would compare us probably more closely to Michigan or Minnesota where they don't have masks dates like we do here in Illinois and they're seeing highest case rates right now."
Pritzker has not made any announcements about whether the state plans to roll back its mask mandate for indoor spaces.
Dr. Allison Arwady, commissioner of the CDPH, has indicated that the city would need to see fewer than 200 new COVID cases per day to roll back the requirement, but last week said the city saw more than double that number in recent weeks.