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The coronavirus is threatening crowded Immigration and Customs Enforcement facilities with long histories of mishandling infectious diseases that can rapidly spread outside their walls, a ProPublica review of thousands of pages of death reports found.

The ICE population presents a particular danger as communities grapple with the novel disease. The analysis found that ICE has repeatedly failed to follow rules meant to contain communicable diseases inside its detention centers, which can become breeding grounds for illness. As guards and nurses leave facilities and go home, those outbreaks can spread.

At a suburban Denver ICE facility, the Aurora Detention Center, 10 detainees have now been quarantined for potential exposure to the coronavirus. An ICE staffer at a New Jersey detention center has tested positive.

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Last year, more than 5,200 detainees were quarantined as ICE tried to contain mumps and chickenpox. An analysis by the Centers for Disease Control and Prevention last year found mumps cases spiked at the same time the Trump administration packed more and more people into close quarters. Most of those detainees got sick while in federal custody, not before, the CDC found.

Problems with handling communicable illnesses inside packed ICE facilities have festered for years. ProPublica reviewed more than 70 reports detailing the circumstances around detainee deaths over the last decade and found medical staff often don’t follow strict rules for testing contagious diseases.

The response to tuberculosis, a respiratory illness that can spread easily in confined and crowded spaces, is a strong indication of how they’ll respond to other contagious diseases, medical experts say.

In a dozen cases ProPublica reviewed, medical experts who were called in to investigate a death in ICE custody raised alarms that staff had failed to follow nationally accepted standards.

ProPublica identified six cases where failures to address communicable disease risks — such as practical nurses with little formal training waiting far too long to notify doctors of ill patients — were later found to have been contributing factors in the deaths of immigrants.

Dr. Marc Stern, a medical expert who used to inspect ICE facilities as a contractor for the Department of Homeland Security, said the crowded conditions in prisons make them prime targets for outbreaks.

“The more people you have, the less social distancing you can do,” Stern said. “These events are going to be harder to manage as staff can’t get to work because they get sick or they have to stay home with their kids.”

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This time last year, after the third outbreak in four months at the Aurora Detention Center, including mumps and chickenpox, Aurora City Council member Allison Hiltz was fed up with the facility’s private management company for not alerting the city.

“They were not reporting their communicable diseases, and that included chickenpox that they had a couple of months prior to that,” Hiltz said.

She pushed through a city ordinance requiring GEO Group, a large ICE contractor, to report public health concerns to the local fire department. At the same time, a rookie Democratic congressman, Jason Crow, demanded access to the facility and called for ICE to conduct monthly inspections. As recently as February, one of those inspections found sickness still raging in the facility, with 68 people quarantined with the flu and an additional 70 with mumps. GEO Executive Vice President Pablo E. Paez said the company follows best practices in managing diseases.

Amid the global coronavirus pandemic, GEO said none of the quarantined detainees in Aurora have been confirmed as sick with the disease.

But Hiltz said GEO must step up its monitoring of the virus.“If you look at what’s happening now, there’s no vaccine for this,” she said. “It only takes one person in a facility like that to spread pretty quickly, and there’s no immunity for the employees who are coming and going and taking their kids to school and grocery shopping.”

In Aurora and across the country, ICE has repeatedly struggled to contain communicable diseases that can spread in ways similar to the coronavirus, the review of death reports found. The reports focused on the medical histories of detainees but do not make clear whether they infected others.

During a medical check up in January 2018, detainee Yulio Castro-Garrido, who worked in the kitchen at the Stewart Detention Center in Georgia, had a fever, rapid pulse, cough and runny nose — flu-like symptoms. But medical staff did not order him to stay in his cell and let him return to the kitchen where, medical investigators later wrote, he could have been “transmitting contagious illness.”

He died the next month, at age 33, of pneumonia and the flu.

Later in 2018, medical screeners at the Otay Mesa Detention Center in California took an X-ray of a 62-year-old woman from Mexico and found evidence of TB. Instead of immediately isolating her, the facility allowed Augstina Ramirez-Arreola to have close contact with other detainees for nearly three hours.

Read More Inside the Cell Where a Sick 16-Year-Old Boy Died in Border Patrol Care Video obtained by ProPublica shows the Border Patrol held a sick teen in a concrete cell without proper medical attention and did not discover his body until his cellmate alerted guards.

She died two months later.

Democrats in Washington have criticized ICE’s spotty record of handling infectious diseases, citing concerns that overcrowding amid Trump’s zero-tolerance policy heightens the risk of a deadly viral spread.

ICE did not respond to questions sent by ProPublica on Tuesday.

On its website, the agency says it has monitored the spread of COVID-19 and has epidemiologists tracking the outbreak and working with staff in its ICE Health Service Corps.

“ICE continues to incorporate CDC’s COVID-19 guidance, which is built upon the already established infectious disease monitoring and management protocols currently in use by the agency. In addition, ICE is actively working with state and local health partners to determine if any detainee requires additional testing or monitoring to combat the spread of the virus,” the website says.

Paez, the GEO spokesperson, said the company is watching out for the new coronavirus and placed the 10 Aurora detainees “under observation.” He did not say whether GEO has tested others under the company’s care.

“Last week, in an abundance of caution, a cohort of 10 individuals was placed under observation as a precaution based on statements made by a visitor to the facility,” Paez said. “None of those individuals have exhibited any COVID-19 symptoms. At this time, all ICE processing centers have discontinued non-legal visitation.”

Meanwhile, civil rights attorneys have petitioned the Trump administration and filed a lawsuit Monday arguing for the release of vulnerable detainees who could potentially get sick inside the country’s crowded immigrant detention system.

Elizabeth Jordan, a Denver-based lawyer who represents Aurora detainees, hasn’t been able to meet with clients as the coronavirus has spread. A lawsuit filed last year by Jordan and a team of immigration lawyers accused ICE of widespread neglect and shoddy medical care.

“With the previous outbreaks, ICE handled it very poorly,” Jordan said. “This has the potential to be orders of magnitude worse.”

At this point, she said, her clients are more likely to get sick from someone bringing the virus into the packed facilities.

“They are sitting ducks,” she said.

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