President Donald Trump has heralded the moves, citing them as necessary to stem the spread of coronavirus. But health experts argue the order invoked in March appears to be intended to halt immigration, not serve a public health purpose.
"We, as a set of colleagues, have been feeling increasingly uneasy on the public health basis," Monette Zard, director of the Forced Migration and Health Program at Columbia University Mailman School of Public Health, said. "It's not looking like a genuine response to Covid and more like immigration policy in another guise."
Columbia University Mailman School of Public Health and Johns Hopkins Center for Humanitarian Health were behind pulling together the letter and its signatories.
"What perhaps you could excuse as a short term emergency measure to reorient procedures and processes has now stretched out for a couple of months," Zard added.
Kennji Kizuka, a senior researcher with Human Rights First who researched the impact of the CDC order on the border, said the "damage inflicted by the order has already been horrific."
"The last thing the CDC should do is renew this illegal and destructive order. The United States has the ability, if it chooses, to safeguard both public health and the lives of people seeking humanitarian protection. The latter does not need to be sacrificed to protect the former," he said.
The letter, addressed to HHS Secretary Alex Azar and Centers for Disease Control and Prevention Director Robert Redfield, highlights sections of the CDC order
that experts consider problematic, including blocking migrants who lack documentation and arrive by land at either the US border with Canada or Mexico from entering the United States.
"It exempts permanent residents and U.S. citizens, and does not apply to tourists arriving by plane or ship -- even though these modes of transportation are explicitly listed by HHS as congregate settings with higher risk of disease transmission than land travel," the letter reads. "The rule is thus being used to target certain classes of noncitizens rather than to protect public health."
Acting Customs and Border Protection Commissioner Mark Morgan has repeatedly said that the restrictions are directly related to the public health risk and not immigration enforcement.
Morgan has suggested that the restrictions would continue to stay in place, even as the United States moves toward reopening.
"From a public health perspective, it has been determined that still is a risk from our borders," he said, referring to the increasing numbers of coronavirus cases and deaths in Mexico. Morgan said the administration is "collectively, across the board continuing to assess, monitor and at that time we'll make the assessment whether that needs to be extended or not."
But new restrictions have also had the effect of largely shutting down the border to migrants, which the Trump administration has tried to do in the past.
Under the stringent border control measures related to coronavirus, only two migrants seeking humanitarian protections
at the border have been permitted to remain in the US, according to US Citizenship and Immigration Services data, which was first reported by The Washington Post.
Customs and Border Protection, the agency tasked with US border security, referred 59 migrants to USCIS, which processes asylum claims, who expressed fear of torture if they were to be returned. Under the new policy barring most migrants at the border, the threshold to be exempted from expulsion is a claim under the Convention Against Torture, according to a homeland security official.
Previously, other asylum claims would be reviewed, but amid the pandemic, the administration has further limited access to humanitarian protections for migrants, claiming it is in the interest of public health.
The border policy gives "asylum applicants a negligible chance of receiving protection in the United States," under the current system, said Sarah Pierce, a policy analyst for the US Immigration Policy Program at the Migration Policy Institute, previously told CNN
. "This administration has completely abandoned their responsibilities to protect vulnerable populations in favor of a policy that provides questionable safeguards against coronavirus."
Health experts recommended instead that US authorities "use evidence-based public health measures to process asylum seekers and other persons crossing the U.S. border." That includes facilitating social distancing and using outdoor space to process migrants at the border, releasing asylum seekers in the US instead of detaining them while they await their court proceedings, and enabling self-quarantine at destination locations.