Governor J.B. Pritzker declared a mask mandate Wednesday for preschool through high school.
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While some parents are opposed to their toddlers having to run around in masks, there could be some unexpected benefits.
The Laurance Armour Day School has provided childcare for Rush University Medical Center employees for 50 years.
They were able to stay open through the pandemic in order for healthcare workers to stay at work, requiring face masks for the kids early on.
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"We were wearing them even before they were mandated," said Maria Walker, program director for Laurance Armour Day School of Rush Univ. Medical Center.
With 90 kids, ages 4-months to 12-years-old, the Walker said in first 15 months of the pandemic, they only had one positive COVID case and none of the typical illnesses they often see.
At the school during the pandemic there's been:
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"The mask has eliminated most of our sicknesses," Walker said. "During this time, it was crucial because parents needed to be at work and they were essential, so we needed to be open for them and having their children healthy here was a benefit to everyone."
"In general, across the board viruses are down," added Dr. Beth Van Opstal.
Dr. Van Opstal is a pediatrician and professor at Rush University Medical Center, and her students often observe at the School.
She said mask wearing has made a difference for children's health and will continue make a difference as kids will increasingly spend more time indoors.
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"I think the risk of not wearing the mask is higher than the benefit to wearing them," she said. "It not just about keeping your own kid safe, it's about keeping all the people in the building and the adults that go with those little people in the building safe."
With a recent increase of children getting COVID a nationwide, staff at the Armour School plan to stay the course. With vigilant cleaning and mask wearing, they hope to continue their success of keeping COVID and other childhood illnesses at bay.