READ: Gov. Pritzker's official 'stay-at-home' order
Joined by Chicago Mayor Lori Lightfoot, Gov. Pritzker said the order begins at 5 p.m. on Saturday, March 21 and will remain in effect through Tuesday, April 7, 2020. It comes one day after the governor of California and hours after his New York counterpart ordered all non-essential workers to stay home.
"I don't come to this decision easily," Pritzker said. "I fully recognize that in some cases, I am choosing between saving people's lives and saving people's livelihoods. But you can't have a livelihood if you don't have a life."
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Essential services - such as grocery stores, gas stations and pharmacies - will remain open, but all non-essential businesses will be forced to stop operating. Pritzker said residents will still be able to leave home to buy food, obtain medication, go to a medical office or hospital, and take walks outside.
"For the vast majority of you already taking precautions, your life will not change very much," Pritzker said.
The governor also said the statewide school closure that was perhaps going to end on March 31, will now be extended to April 7. On Thursday, Lightfoot extended the closure of Chicago Public Schools until at least April 20.
WATCH: Mayor Lightfoot describes how 'stay-at-home' order will impact Chicagoans
Lightfoot added that the CTA will remain running through the "stay-at-home" order, and essential city services, such as garbage collection, will continue. However, all Chicago Park District facilities and libraries will close while the governor's order is in place.
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Pritzker also announced a 5th death in Illinois from COVID-19, a Cook County resident in her 70s. As of Friday, there are 585 cases of COVID-19 in Illinois, a jump of more than 100 cases from the previous day's tally of 422.
The governor said this order is not one he takes lightly and one that was made after talking to health care experts, mathematicians and looking at the modeling for what will happen without taking this drastic action. Pritzker said he enacted the order to avoid the "loss of potentially tens of thousands of lives."
"Left unchecked, cases in Illinois will rise rapidly," Pritzker said. "Hospital systems will become overwhelmed. Protective equipment will become scarce and we will not have enough health care workers or hospital beds or ventilators for the overwhelming influx of sick patients."
Lightfoot then laid out what the city of Chicago is doing to prepare hospitals for more coronavirus cases in the days ahead.
"Our city - in the absence of leadership from the federal government, frankly - is doing the following: finalizing and securing quarantine and isolation locations, bolstering hospital capacity, supporting our health care workers and first responders, and doing everything possible to relieve the pressure on them. And we're building a supply chain to make sure that critical equipment to the health care system - things like ventilators and PPEs - are available and given to areas of need."
Medical experts agree the "stay-at-home" order is critical to stemming the spread of the novel coronavirus.
"Why ask so much of people for just a few hundred cases? Because it's the only way to save those lives," said Dr. Emily Landon, of University of Chicago Medicine. "And now is the time because the numbers you see today in the news are the people that got sick a week ago. And there's still people today who got sick today, who haven't even noticed that they've been sick yet.They picked up the virus, and it will take a week to see that show in our numbers."
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While many offices will have to shift to remote working arrangements, the governor's order will allow restaurants to remain open for pickup, delivery, carryout and drive-through service. The interstates, tollway and local roads will remain open to travel as will airports.
"This is not a lockdown or martial law," Lightfoot said. "As the governor said and I want to reiterate, Chicago's grocery stores, pharmacies and clinics will remain open and there's absolutely no need to change your normal purchasing patterns. What I mean is, do not take this direction as a reason to run to the stores, buy everything in sight, and hoard vital supplies."
WATCH: Stores in Chicago's Gold Coast boarded up ahead of 'stay-at-home' order
On Friday night, the swankiest of the stores on Chicago's Gold Coast closed up shop in the most dramatic fashion. From Prada to Dior, by Saturday evening just about every store on the block will be shuttered by state order.
"It's a ghost town," said Gold Coast resident Dustin Pickett. "It's as if no one lives here. It's insane."
The governor also gave the indication that the "stay-at-home" order could be extended, but did not lay out any specifics. As for enforcement, Lightfoot said police will not be arresting anyone, but may approach people and ask them to go home. She said she believes most residents will comply with the order, as many already are staying home.
Meanwhile, the Illinois Department of Public Health said the state is working to increase testing capacity by working with Illinois hospitals to implement testing within their facilities.
Additionally, the state is working with the U.S. Department of Health and Human Services, Wal-Mart, and Walgreens to set up drive-thru testing sites in the hardest hit areas of the state. These facilities will focus on senior citizens, first responders, and health care workers.
The Illinois Department of Public Health has created a hotline at 1-800-889-3931. More information can be found at the IDPH website and the Chicago Department of Public Health website.