Update June 14: ICE said it has found a total of 297 confirmed cases in 39 ICE facilities from Sept. 2018 until June 13, 2019.

Immigration and Customs Enforcement has so far failed to contain a growing health crisis spreading among migrants held in its detention centers.

The agency first reported to the public in early March that it had identified over the past year some 236 “confirmed or probable” cases of mumps in its detention centers across the country, compared to zero cases the previous year. ICE has not updated the public since then. A Quartz investigation found that the disease has spread in recent months, affecting detention centers across multiple states.

The findings build upon a private spreadsheet shared with Quartz that was started by a group of attorneys, led by the Nashville-based civil rights and immigration lawyer, R. Andrew Free. They have been tracking quarantines in ICE detention facilities since March and have so far identified more than 30 facilities nationwide where clients said they have been quarantined for mumps and, in some cases, chickenpox.

To tally the full breadth of detainees who have caught the disease, Quartz contacted the state and county health departments that oversee each of the facilities where immigration lawyers reported outbreaks. Not all of those departments monitor outbreaks of disease in ICE facilities. Most notably is Louisiana, where there is no local oversight of its rapidly expanding immigrant detention system. Authorities in California—where state officials cut ties with ICE, removing a layer of oversight—also said they had no data on disease in ICE facilities.

Despite the difficulty of obtaining exact numbers, even partial figures show that ICE is facing a persistent problem.

In Texas alone, since October 2018, some 300 migrants have been diagnosed with mumps in the state’s federal immigration facilities, including ICE and border processing centers. More than half of those cases came in 2019. Meanwhile, the disease has spread to ICE immigration facilities in at least 11 other US states. In some of those cases, the disease has spread to local populations, according to immigration activists and public health authorities.

In Arizona, where ICE holds about 3,000 migrants, the epidemic is so serious that local health officials have launched an official investigation into its spread. After an outbreak in Aurora, Colorado earlier this year, local health authorities scrambled to help vaccinate 1,100 detainees and 200 staff. The same facility just reported a new case of mumps in late May. An immigration detention center in Georgia, which has more than 1,000 beds, just dealt with its second infestation of mumps this year.

Mumps is a viral disease that affects the salivary glands, causing painful swelling. While it spreads quickly and can sometimes have serious complications, such as hearing loss, it is not fatal and is easily prevented through vaccination. But the spread of the disease through ICE facilities suggests the overburdened US immigration system is under-prepared in the event of a more serious health problem, like measles or another deadly communicable disease.

The Trump administration’s crackdown on immigration has funneled a rush of asylum-seekers from Central America, as well as other migrants, into overstretched processing and detention centers around the country. Many of these migrants will be forced into detention for long periods of time as immigration judges sift through the hundreds of thousands of pending cases.

Several children have died in recent months of illness while in immigration custody, or soon after being released. Flu outbreaks are rampant. Attorneys at the Southern Poverty Law Center told Quartz that migrants sometimes go without medical care because of a shortage of doctors and nurses at some detention centers.

Meanwhile, the Trump administration is threatening to cut development aid, like programs to fight gang violence and poverty, to the very countries migrants are fleeing—a move Central American officials and international aid groups expect to drive even more asylum-seekers to the US border.

“What doctors are seeing is the downstream consequences of terrible policy distorted by partisan politics,” said Irwin Redlener, a pediatrician advising the Department of Homeland Security (DHS), which oversees most of the US immigration system, on how to stop people in its care from from getting sick or dying. “This whole situation needs to be overhauled.”

This crisis, meanwhile, is unfolding while the senior management of ICE, and in fact most of the US immigration system, is in flux after a White House-led purge of the DHS.

Quarantines and due process

In its effort to prevent the spread of the disease in its facilities, ICE has enforced widespread, rolling quarantines that can put thousands of detainees on lockdown for weeks. It’s a move that has given rise to a whole other serious problem.

If one person in a housing unit tests positive for an infectious disease like mumps, ICE often quarantines the entire group for the duration of the incubation period, which is about 26 days, immigration attorneys and health officials told Quartz. Any new cases that appear during this time trigger a reset of the quarantine period, which means it then starts all over again.

While under quarantine, those detainees cannot meet with their lawyers, nor are they usually allowed to attend court proceedings, such as bond and asylum hearings, leading to prolonged detention and a denial of the rights US law guarantees asylum seekers.

Darwin Antunez Ramos, a 33-year-old asylum seeker from Honduras has been held at the Adelanto Detention Center, a privately-run facility in southern California, since December 2018. His attorney, Wallie Mason, said she believes quarantines are not always medically necessary, and are sometimes in fact used by guards to punish detainees who complain or step out of line.

Free, the Nashville immigration lawyer, said this happened to Wilhen Barrientos, a client of his being held in a private detention facility in Georgia. According to a lawsuit Free filed on behalf of Barrientos, guards quarantined him for chicken pox shortly after he filed a grievance against an officer for forcing him to work while he was sick. However, Barrientos informed the staff that he had contracted the virus as a child and was unlikely to get it again. Guards nonetheless placed Barrientos in quarantine for two months.

Antunez, meanwhile, was quarantined with mumps for the past month and was finally released from segregation on May 25, Mason told Quartz. After an outcry, the Adelanto facility allowed lawyers to video-conference with their clients.

Mason also said Antunez told staffers at Adelanto that he wanted to be vaccinated, but was told it was too expensive. A healthcare provider at Adelanto who was trying to help Antunez get his shots is no longer working there, Mason said, adding that she is frustrated by the lack of information available to her.

“GEO, the private company that runs that place, just has so many layers of bullshit and obstacles for you to know anything that’s going on,” she said.

Adelanto is one of multiple ICE detention facilities run by a private prison company. The US government pays hundreds of millions a year to the GEO Group and CoreCivic to detain migrants, making the system even less transparent.

Quartz reached out to GEO and CoreCivic for comment but both companies referred all questions to ICE. ICE referred Quartz to the agency’s detention standards manual, which says each facility should have a written plan “for the identification, surveillance, immunization, follow-up and isolation of patients” who may have communicable diseases. ICE offers guidelines to contractors who are supposed to follow them, but there are few repercussions if they don’t, a recent internal investigation found.

Brendan Raedy, an ICE spokesman, told Quartz in an emailed statement that ICE is committed to ensuring everyone in their custody gets “timely access” to medical services and equipment.

“Detainees in US Immigration and Customs Enforcement (ICE) custody can come from countries where communicable diseases are less controlled than in the US, thus carrying with them the risk of spreading infection. Because of this risk factor, ICE takes precautionary measures to mitigate potential exposure to others in the US, including those in ICE custody,” he said.

He added that ICE detainees receive medical, dental and mental health intake screening within 12 hours of arriving, and have access to 24-hour emergency care. “Comprehensive medical care is provided from the moment detainees arrive and throughout the entirety of their stay. ICE spends more than $269 million annually on the spectrum of healthcare services provided to detainees.”

A nonexistent system

The US immigration detention system is the world’s largest, according to the Global Detention Project, a nonprofit that promotes human rights for migrants around the world. State health officials say this sprawling bureaucracy follows no national standards for vaccinating migrants as they enter the country, and there’s no public health agency that serves as a watchdog for the overall immigration system.

The US Bureau of Justice Statistics collects information about the health and medical care of convicted criminals in detention, but not migrants. A spokesperson for the Center for Disease Control told Quartz the agency relies on state health departments for information. But several state health agencies Quartz contacted said they had no oversight of ICE facilities.

“We ignore that population in any national health statistics,” said Marc Stern, an associate professor of health services at the University of Washington, and former Washington State Department of Corrections health official.

Local health authorities tasked with keeping civilian populations in their areas safe said they have no idea how widespread the mumps epidemic is in immigration facilities around the US. They don’t even know who would know.

“I have no idea to what extent ICE may be tracking this,” said Bernadette Albanese, medical epidemiologist with Colorado’s Tri-County Health Department, which oversees the Aurora facility. It’s difficult, she told Quartz, for a local health department to trace how the disease arrived in its state. “We don’t have data on where the detainees are coming from, that is privileged data.”

Mumps quarantines in ICE facilities are being enforced as far north as Michigan. A group of migrant women sent to a county jail in the state were “exposed on a plane,” a Michigan department of health spokeswoman said. “They were all isolated/quarantined together and wore masks if around others,” she said.

State officials in Georgia said they think the two separate outbreaks they’ve faced in recent months can be traced to an ICE processing facility in Texas. But no one can say for sure. The latest outbreak, which began last week, has infected eight people so far, including one employee, a Georgia Health Department spokeswoman said. Two Georgia ICE facilities also have cases of chicken pox.

A growing problem within a growing problem

The detainee population has climbed from 39,000 at the end of 2015 to a record 52,000 in May. The growing numbers are the result of the Trump administration’s zero tolerance policy, which forces asylum-seekers into detention.

The majority of migrants in ICE detention—about 60%—have not been convicted of any crime, according to the latest figures from Syracuse University’s Transactional Records Clearinghouse. But they remain forcibly detained for weeks or months in a patchwork of privately-run facilities, local sheriff’s offices, and federal detention centers, sometimes after being flown across the United States from another federal facility.

Those fast growing numbers mean that finding a way to manage a health crisis within these facilities is all the more urgent. “It’s a burgeoning public health crisis,” Rep. Jason Crow, a Colorado Democrat whose district is home to the Aurora ICE facility, told Quartz.

In any institutional setting, whether it’s a prison or a long-term care facility for the elderly, there are certain precautions you generally take when there’s an outbreak of something contagious, said Redlener, the pediatrician advising the Department of Homeland Security. You make sure everyone is immunized, and you isolate the people who have immunity from those who don’t, he said.

But Redlener said the sheer number of people coming across the border has caused that process to break down. The Inspector General of DHS said in a report last week that at one Customs and Border Protection center in Texas there were 900 migrants detained in a facility meant to house 125 people. “You put them in tight, closed crowded conditions, and you really have an epidemic control problem,” Redlener said.

The US government created ICE in the aftermath of the Sept. 11 terrorist attacks. A part of the massive Department of Homeland Security built in response to those attacks, the central mission of ICE at the time was to help prevent terrorism by “targeting the people, money, and materials that support terrorist and criminal activities.” This included removing people in the country who were believed to be threats.

Even before Trump pushed for increased detention for immigrants, though, ICE had grown into a detention and deportation machine with a $6 billion annual budget. It has long relied heavily on for-profit prison companies to help manage the huge numbers of migrants it detains. As the mumps cases outbreaks show, those private companies don’t always answer to public health departments. Medical care for detainees is often further subcontracted out. Areas like rural Louisiana, which nearly doubled new ICE contracts since September of 2018 to offset emptying prisons after civil justice reform, don’t always have enough residents living nearby to properly staff facilities.

Lisa Graybill, the deputy legal director of the Southern Poverty Law Center, told Quartz that there is no oversight at the local official level, at the federal level, or at the contractor level. But more importantly, she added, “the whole point is most of these people don’t need to be detained, not by law or by public safety interests.”

Despite calls for more oversight, the Trump administration has so far rejected requests from members of Congress who want to monitor facilities within their own jurisdiction.

“We’ve been met with complete silence,” Crow said. “They are not welcoming any sort of scrutiny, which is really troubling.” Congress has a “constitutionally-mandated authority to conduct this oversight and they’re not allowing us to do it,” he added.

Crow introduced a bill on May 20 that, if passed, would require ICE to allow members of Congress into its facilities upon request.