The city so far has drawn down and sent out 501,000 of the very hard-to-find N95 masks, according to Arwady’s office, even as other officials gripe that they can’t get enough. An additional 720,000 have been reserved for possible use in the emergency hospital facility at McCormick Place. That still leaves more than half of the city’s original stock of 3.9 million as the pandemic continues to unfold.

“We talk to the hospitals every single day” to see what they need, Arwady said. “We’re situated a lot better than a lot of other places.”

The city also has distributed 2.4 million sets of gloves, 124,000 protective gowns and 1.2 million other masks, she said. And more is coming in all the time, since the city continues to receive regular orders from suppliers with which it has had long-standing relationships.

“We are grateful for the tens of thousands of units of PPE, including N95 masks, provided by the city of Chicago for our team members’ use at Advocate Illinois Masonic Medical Center and Advocate Trinity Hospital,” says Advocate Aurora Health spokeswoman Brigid Sweeney. “We appreciate the role CDPH has played in keeping us adequately supplied,” says a spokesman for Rush University Medical Center.

Even Cook County, which had its own, smaller reserves, has tapped the city for help getting materials for its network of hospitals and health centers. “We appreciate the ongoing cache of supplies sent by CDPH and other agencies, who have supported us through the initial weeks of this crisis when everyone’s PPE supplies were very limited,” a county spokeswoman said.

So what went right here?

According to Arwady, city health officials for years have allotted a portion of their federal funds to acquire PPE and related materials, saving up for the proverbial rainy day.

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“Every month, we talk about what our supply is, what we need to get,” she said. It also probably doesn’t hurt that before joining the city and being made commissioner by Mayor Lori Lightfoot, Arwady worked for the U.S. Centers for Disease Control & Prevention, the national command center for anything that has to do with fighting infectious diseases.

Arwady said the only item the city was short of initially was ventilators. It had 150 but needed 300 more, something she said it was able to obtain, in two batches, by requesting them from federal officials.

Arwady was tactful when I asked whether other jurisdictions should have done what Chicago did in stockpiling material.

“Let’s just say I’m glad the city did,” she said. “I’ve never been as glad that, here in Chicago, we took this seriously.”

Of course, that depends on what happens now. “April will be the moment of truth,” she said. “We're hoping by the end of the month that we’ll be seeing the peak.”