CHICAGO (WLS) -- From the city to the suburbs, protests calling for justice for George Floyd have brought thousands of people into very close proximity to each other, some wearing masks and others not.
The crowds prompted a warning about COVID-19 from Mayor Lori Lightfoot and Chicago health officials.
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"Whether you were out there for legitimate and righteous reasons, or for some other, you have put yourself at risk," Lightfoot said. "That risk is real. It is present, and it will be with us for the foreseeable future."
While the case and death numbers have gone down, doctors on the COVID-19 front lines fear the protests are a perfect storm for a surge.
"There can definitely be spread between people in the protest, between people trying to protect people in protest and those reporting on the protest, and they can bring it back to their communities," said Dr. Michelle Prickett, Northwestern Medicine.
Prickett said all it takes is one asymptomatic protester or police officer with a high viral load to spread it to three more people, who bring it home to their families and the spread continues.
Doctors fear a surge can overwhelm the health care system. Right now there are about 40 COVID-19 patients in Northwestern Memorial Hospital's ICU; that may seem like a lot, but doctors say it's down to a manageable level compared to a few weeks ago.
Testing is key to controlling the virus; the protests forced the state to close some drive-thru test sites, which doctors said is not helping the situation.
"I feel like people's voices need to be heard, whether or not it's in that traditional form is the question," Prickett said.
Prickett said masks only work if everyone at a protest wears one, but there is concern because there has been no testing on how droplets from yelling and shouting can go through masks.
Chicago protests could spark coronavirus case surge, doctors and health officials warn