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Chicago making strides against coronavirus, data shows; Lightfoot says ‘we’re not where we need to get’

New City Hall data includes ‘anonymous’ tracking of residents’ mobile devices since the stay-at-home order.

The Chicago economy is being hit hard by the global pandemic, and the cost is likely to exceed half a billion dollars, according to the city’s chief financial officer.
Amid fears of the coronavirus pandemic and a stay-at-home order from Gov. J.B. Pritzker, Daley Plaza sits nearly empty in the Loop, as seen from the roof of City Hall earlier this month.
Ashlee Rezin Garcia/Sun-Times

Chicago made significant progress to slow the spread of the coronavirus in the first month since the disease upended life here and across the country, but the continued rise of the virus means Mayor Lori Lightfoot is not ready to return the city to normal.

That’s the message delivered by City Hall as it publicly released new data related to the virus Wednesday, including numbers that show how well Chicagoans are sticking to Illinois’ stay-at-home order based on “anonymous” data from potentially hundreds of thousands of mobile devices.

While there are some reasons for optimism, Lightfoot and Public Health Commissioner Dr. Allison Arwady told reporters they are still waiting to see the number of new coronavirus cases level out and decline before revisiting the stay-at-home order issued by Gov. J.B. Pritzker. For now, they said, the virus is still on an upward trajectory.

“We are making progress,” Lightfoot said. “We’re not where we need to get in terms of thinking about, in my view, lifting the stay, although ultimately that’s the governor’s call. But we do think it’s important to let Chicagoans know why staying home is not just a catch phrase, but it’s something that we believe is vitally important from a public health standpoint.”

The new data revealed that roughly 40% of the beds in Chicago’s intensive care units are currently occupied by coronavirus patients, while the overall capacity of the city’s ICUs has grown by about 200 beds since the start of the pandemic. It also shows a quarter of the city’s ventilators are being used by coronavirus patients. Overall, half of the city’s ventilators are still available.

Even as the number of hospitalized coronavirus patients increased, Chicago’s ICU capacity has kept pace and not been overwhelmed like in other cities. On average, ICU beds have been 74% occupied over the last four weeks. Arwady said that hospitals in Chicago have been able to maintain the ICU occupation rate by converting spaces into additional ICU beds and halting elective surgeries.

Even as the number of hospitalized COVID-19 patients has increased, Chicago’s ICU occupation rate has not risen above 79%, showing how hospitals have kept pace with demand.
Even as the number of hospitalized COVID-19 patients has increased, Chicago’s ICU occupation rate has not risen above 79%, showing how hospitals have kept pace with demand.
Caroline Hurley/Sun-Times

To view an interactive version of this graph, click here.

On the whole, the city has gone from doubling its coronavirus cases every two days back in March to now doubling its cases only every 12 days. The effect is a crucial flattening of the coronavirus “curve” needed to help protect the health care system from being overwhelmed.

The data also suggests the virus slowed as a result of Pritzker’s stay-at-home order, which went into effect March 21, as well as the city’s closure of its parks five days later. Had it stayed on its previous trajectory, the city might now have seen as many as 62,464 coronavirus cases and 2,000 coronavirus deaths, according to City Hall.

Instead, as of Tuesday, the city had 9,666 coronavirus cases and 347 deaths.

Pritzker expressed his own guarded optimism about the deceleration of the coronavirus Tuesday, telling reporters that “we are, in fact, bending the curve.” But he warned “this curve may not flatten. And it may go up again if we don’t adhere to the stay-at-home order. We need to stay the course for now for our efforts to truly remain effective.”

Before measures were taken to slow the spread of coronavirus, Chicago was on pace to double its cases every two days. Now, after stay-at-home orders and social distancing guidelines went into effect, Chicago is only doubling its cases every 12 days.
Before measures were taken to slow the spread of coronavirus, Chicago was on pace to double its cases every two days. Now, after stay-at-home orders and social distancing guidelines went into effect, Chicago is only doubling its cases every 12 days.
Caroline Hurley/Sun-Times

To view an interactive version of this graph, click here.

Their comments both came as President Donald Trump showed interest this week in “reopening” certain parts of the country before the end of the month.

Asked about a return to normal, Lightfoot said, “think about a world in which you go back to work. When are you going to feel comfortable?”

Key to that answer, the mayor said, is a “widespread testing regime” where employers and individuals can be confident the virus will not spread among themselves, their colleagues or at large public gatherings such as a concert or a sporting event.

“We’ve got to have a lot more confidence that there’s a testing regime that we can rely upon that is widespread,” Lightfoot said. “We’re going to have to think about how that extends out, not just to people going and getting a clinical test, but what are the measures that have to be in place in these environments where people gather to give us confidence that we’re not going to see a huge spike in cases again?”

Perhaps most intriguing about the new data released by the city is the use of mobile devices to track and determine that Chicagoans are, for the most part, adhering to the stay-at-home order. Lightfoot and Arwady said the information was provided by the risk software company BlueDot through the data collection company SafeGraph. They characterized it as “anonymous” data gathered from users of mobile device applications who agreed to let certain applications track their locations.

“We don’t know, nor would we get, specific information about cell phone users,” Lightfoot explained. “So I don’t think there’s any privacy issues. And it’s dependent upon one’s use of applications and then allowing access related to location.”

Arwady said potentially “hundreds of thousands” of mobile devices were tracked as part of the study. A check-in occurred on each of those phones every half-hour, she explained. The study assumed the device’s most common location between midnight and 9 a.m. was its “home.”

From there, the median weekly proportion of device check-ins within 200 meters of the home went from 59% in late February to roughly 70% when the stay-at-home order went into effect. The number grew to as high as 79.2% in early April.

Those numbers were higher on the North Side, where the percent of check-ins at home last week ranged from 80% to 90%. Elsewhere in the city, the numbers tended to range from 70% to 80%.