CHICAGO (CBS) — Officials announced Saturday that Cook County Sheriff Tom Dart has tested positive for the coronavirus.

He is not sure where he contracted COVID-19, but for months, Dart has been trying to keep cases under control at the Cook County Jail. And as CBS News’ Adriana Diaz reported, Dart said he has had success despite a recent uptick.

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This spring, more than 300 inmates had COVID-19 at the Cook County Jail, and the cases were climbing. Medical director Dr. Connie Mennella had to keep them alive.

“I’ve described it previously like war, and we were in this fog of war,” Mennella said of the conditions early on in the outbreak.

In the war against COVID at the jail, Mennella and Dart are the commanders. They have seen the virus ravage their ranks and take 12 lives – eight inmates and four staff.

“There was no playbook. That was a killer,” Dart said, “and so we were making things up as we went along.”

The improvisation worked. As Chicago’s curve sloped upward this spring, the jail’s fell off a cliff. When we visited in August, there were just 15 cases.

Diaz: “I read that you said we didn’t just bend the curve.”

Dart: “We exploded the curve. I mean, there’s no curve.”

Diaz: “How did you do that?”

Dart: “We made the determination at the outset we were going to be driven by science.”

And they went all in – with universal mask-wearing and temperature checks. A total of 1,500 detainees were also released early – due in part to pressure from inmate advocates – which helped reduce the population.

Meanwhile, closed buildings were also opened to spread the rest of the inmates out.

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But onsite rapid testing machines proved the most potent weapon. New inmates are tested, and regardless of their test results, they are all quarantined.

“That’s been a huge part of our containment,” Dart said. “If you’re new, you get tested. If you come back from a hospital, you get tested. If you come back from other counties, you get tested. Test, test, test. We are doing a lot of testing.”

Real-time testing allowed for real-time reaction, which jail officials believe saved lives.

Inmate Santa Paz, who was brought in on a gun charge, tested positive at the height of the outbreak.

Paz: “The headaches were really bad. So, you know, and then the people around me that we’re even sicker.”

Diaz: “Are you nervous knowing that your around so many people in a confined space in a pandemic?”

Paz: “It scares me a little, because if one guy gets sick, everybody else is going to get sick. We try to practice social distancing, but where I’m at, it’s kind of hard.”

“There isn’t this wild spread going on in the jail, no,” Dart said recently. “This has been contained and under control for months.”

But now as Chicago, like much of the country, is seeing huge spikes in COVID cases, positive cases in the jail have quadrupled in the last two weeks. The jail’s positivity rate is now about 4 percent, compared to 2 percent this summer.

“We may have barbed wire. We may have brick walls. They are porous,” Mennella said. “What happens in the community greatly impacts the jail. We have COVID fatigue, and that has allowed this virus to take hold.”

In this latest surge, the sheriff and the doctor worry they may not be able to keep the virus outside to protect their inmates inside.

Earlier this month, Dart suspended in-person visitation at the jail because of the recent uptick in cases.

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CBS 2 Chicago Staff