In the press conference with Chicago Department of Public Health Commissioner Dr. Allison Arwady, Lightfoot said Chicago is in a second surge of COVID-19 cases.
Mayor Lightfoot said Monday that the average daily case count for Chicago is 561, up 50% since last week. On June 22, days before the move to phase four, the number was 167. Chicago's positivity rate stands at 5.4%.
"Now is the time to double down on what we know works and come together as a city to flatten the curve once again," Lightfoot said. "Everyone must do their part to keep themselves and others safe and help us overcome this deadly disease."
If the city rolls back, it is not waiting for the 8 percent positivity rate limit the state has set. Through case investigations and contact tracing, the city said surprisingly the new spread is not coming from public places like schools, public transportation or restaurants.
"Where we are seeing spread are not the spaces we regulate as a city," Arwady said.
Mayor Lightfoot and Dr. Arwady reiterated calls to continue to use face coverings and limit social gatherings, even small ones.
"I'm deeply concerned about these trends and worried that we've got some COVID fatigue setting in where people are not following the public health guidance as they should. This virus doesn't care who you are, it's just looking to spread, and if we give it the opportunity to do so it will," said Dr. Arwady. "Most troubling is the fact that COVID-19 continues to have a disproportionate impact on Black and Latinx individuals, and those with under-lying medical conditions. But we're seeing a rise in cases across the city and across all races and ethnicities, so we all need to re-dedicate ourselves to combatting this epidemic."
WATCH: Mayor Lightfoot warns of sharp increase in COVID-19 cases
Not only did Dr. Arwady say the city is registering increases in every age group, every demographic and every part of the city, she said that despite fears of contracting the disease from strangers, two out of three people in Chicago who have gotten COVID-19 got it from someone they know and three out of four of those contacts happened at home.
Dr. Arwady said in gatherings of ten people, there is a 14% chance someone in the group has COVID-19.
"Do not invite anyone over to your house or apartment. This is not the time for non-essential gatherings," Arwady said.
Even with the holidays coming up, the mayor and her health commissioner are begging Chicagoans to double down follow all the protocols and limit the number of people in your home.
"This is a time for each of us to dig down deeper and be more diligent," Lightfoot said.
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The update comes as the number of COVID-19 cases across Illinois has been on the rise, with the positivity rate for the state rising above 5%.
"I think a lot of us in the healthcare system were overwhelmed by the first wave of COVID, and to see it starting up again is really scary," said Dr. Nancy Glick, with Sinai Health System.
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The update also comes after Chicago Public Schools announced a plan to bring early childhood and special needs students back into the classroom later in the second quarter.
The Chicago Teachers Union has pushed back against the plan, calling it risky.
CPS Chief Education Officer LaTanya McDade joined ABC7 Monday morning to discuss the plan.