Migrants don’t carry more viruses than anyone else

The pandemic has renewed rhetoric on immigration as a public health threat. But research doesn’t support that.

Lourdes Medrano is a freelance journalist whose work has been featured in The Christian Science Monitor, The Washington Post, and Wired. This story originally featured on Undark.

On a crisp morning last fall in Tijuana, Mexico, psychologist Diana Hernández knocked on the metal doors of Movimiento Juventud 2000, one of several migrant shelters in this border city. Hernández was there as part of a four-person team of municipal workers tending to the needs of some of Tijuana’s thousands of migrants whose lives are in limbo while they wait to request asylum in the United States or to attend the court hearings that will determine the fate of their asylum requests.

A security guard opened the doors, and the group entered the shelter—essentially, a large room with tin walls, a concrete floor, and a partial roof. A group of preteens huddled over a nearby table, playing Serpientes y Escaleras, a board game similar to Chutes and Ladders. Farther back, the shelter was filled with row upon row of small camping tents. Just outside one tent, a woman who appeared to be in her mid-30s folded clothes. Farther back, a gray-haired woman cradled an infant and paced. Altogether, this particular shelter housed roughly 100 migrants, at least 30 of them children, mostly from Central American countries.

Hernández gathered children for a workshop while her colleagues, including two physicians, took their places at a long table in the center of the room. They’d brought a box of medical supplies, including antibiotics, antihistamines, and pain relievers. Soon, mothers started lining up for consultations. One 4-year-old boy who had been at the shelter for two months was experiencing an outbreak of hives. The doctors, suspecting an allergy to soap or laundry detergent, gave his worried mother medication to help with the symptoms.

As the hours ticked by, most of the cases turned out to be respiratory illnesses, allergies, and stomach problems. In addition, Hernández met with migrants living with depression and anxiety. But pressing as these issues are, this constellation of comparatively benign health problems stands in marked contrast to longstanding fears—frequently stoked by anti-immigration interests—that migrant populations here and around the globe carry a wide array of communicable diseases, and therefore pose a threat to public health in destination communities. “We have these individuals coming from all over the world that have some of the most extreme medical care in the world,” said David Ward, a former agent with U.S. Immigration and Customs Enforcement, in a 2018 interview on Fox News. “And they’re coming in with diseases such as smallpox and leprosy and [tuberculosis] that are going to infect our people in the United States.”

Tents set up for migrants staying at the Movimiento Juventud 2000 shelter.
Tents set up for migrants staying at the Movimiento Juventud 2000 shelter. Lourdes Medrano

Such assertions have frequently surfaced under the administration of U.S. President Donald J. Trump—and perhaps no more so than amid the global COVID-19 pandemic. Indeed, last month, Trump effectively shut down the country’s asylum system and began sending thousands of migrants to Mexico in an effort to combat the novel coronavirus. And this week, he vowed to temporarily halt all immigration to the US, with the exception of seasonal workers and some green card seekers. The most recent move triggered immediate debate over whether the president even had the authority to proceed with such an order, but its underlying premise had a clear fidelity with anti-immigration rhetoric of years past: “Tremendous infectious disease is pouring across the border,” then-candidate Trump proclaimed in 2015, adding that the US had become a “dumping ground” for immigrants carrying all manner of illnesses.

The science, however, has long suggested otherwise. Although there have been historical instances of immigration-related disease transmission, such as when European colonizers imported diseases like yellow fever and smallpox that infected Native Americans, studies reaching back decades have repeatedly found no link between modern migration and the importation of infectious disease to host populations. Even the World Health Organization disputes this trope, pointing out, for example, that more than 100 countries, including many in Latin America, have higher vaccination rates for common diseases, like measles, than the US.

“People have this fear that somehow these refugees are going to bring some virus,” says Helen Perry, executive director of Global Response Management, “and that’s just not really founded in any kind of reality.”

What is true, public health experts say, is that there is a great need for medical services among migrant populations like those at Movimiento Juventud — not because they pose a threat to the countries where they seek asylum, but because so many of them face harsh and unhealthy conditions in their home countries, on their journeys, and in the shelters and tent encampments that stretch along the U.S.-Mexico border. “We come across people who arrive here without having slept, without having eaten,” said Hernández. “Some have an illness, or they’re stressed and in mourning over having been uprooted.”

The need for basic health services had already begun soaring in December 2018, when the Trump administration announced the Migrant Protection Protocols (M.P.P.)—commonly known as “Remain in Mexico”—a policy that requires any migrant applying for asylum in the U.S. to wait in Mexico for the duration of their legal proceeding, which can last several months, or in some cases years. When the U.S. adopted the new protocols, federal officials said medical exemptions would be available for the severely sick, but recent reporting suggests this has not been the case. And while the M.P.P. program has faced legal challenges, being blocked by a federal court of appeals in California, that decision was eventually reversed, and most recently, the Supreme Court decided to keep the program in place.

In recent months, migrants have lingered even longer in shelters at the border, further delayed by the COVID-19 crisis. Several of the holding facilities—including Movimiento Juventud—have now shuttered or begun turning away would-be asylum seekers, leaving those currently in their care to languish in limbo for still longer. And while the current pandemic will eventually run its course, immigration health advocates are now grappling with the realization that the new protocol is here to stay, suggesting that the influx of migrants will continue to strain the resources of local governments in Mexican border cities.

Migrants “pray to not get sick,” said Psyché Calderón Vargas, a physician who volunteers in Tijuana’s migrant shelters.

But, she added, such living conditions force migrants to gamble with their health every day.


Global response management provides emergency medical services in countries wracked by war, disaster, and conflict, including Iraq, Syria, and Yemen, and it now runs a clinic for migrants at a tent encampment in the Mexican border city of Matamoros, Tamaulipas. Despite medical advances that have put an end to such deadly diseases as smallpox and nearly eradicated many others, Perry and other experts note, the perception of migrants as disease carriers lingers—and it is one that transcends borders.

In Tijuana, a vocal segment of the local population asserted that asylum seekers arriving in the city from Central America posed a health risk. Similar sentiments in the Mexican border city of Mexicali prompted close to 500 people to demonstrate this past September against the planned opening of a migrant shelter in their neighborhood. And in Italy last year, amid efforts to clamp down on asylum seekers, the government prevented a ship from docking because of health fears connected to the roughly 80 African migrants onboard. Four years earlier in Norway, health authorities had to assuage fears after some residents took to wearing latex gloves in public for infection prevention after a surge of refugees and migrants arrived from Syria, Afghanistan, and Iraq.

For all the concern, however, the evidence tells another story. A sweeping 2002 study, titled “The Foreignness of Germs: The Persistent Association of Immigrants and Disease in American Society,” found that the “social perception of the threat of the infected immigrant was typically far greater than the actual danger” as immigration into the United States rose in the late 19th and early 20th centuries. “Anti-immigrant rhetoric and policy have often been framed by an explicitly medical language, one in which the line between perceived and actual threat is slippery and prone to hysteria and hyperbole,” wrote the study’s authors, researchers at the University of Michigan. Medical inspections of arriving immigrants were “often predicated on the prevailing racial and class stereotypes,” the study also noted. Mexican and Chinese laborers, for example, were more likely than affluent immigrants to experience medical scrutiny. For example, they were more frequently required to give blood and urine samples, and they were more likely to be disinfected with kerosene and other chemical agents.

Another study, published in The Lancet medical journal about a month after the arrival of the largest Central American caravan in Tijuana in late 2018, also debunks the myth of the disease-spreading migrant. An analysis of 96 studies involving more than 15 million international migrants found that while diseases such as hepatitis, HIV, and tuberculosis are more prevalent among migrants, infection tends to be contained within migrant communities, rather than spread to the general population. “There is no systematic association between migration and the importation of infectious diseases,” the study authors stated in an interview. Early last year, the World Health Organization released a report highlighting “a very low risk of transmitting communicable diseases from the refugee and migrant population to the host population.”

Indeed, in today’s global economy, disease is far more likely to spread through business and leisure travel than through an influx of migrants or refugees, says Perry, who is also a nurse. She points to the current spread of COVID-19, which originated in China and has now spread throughout the world. Certain communicable diseases can thrive among people who live in close quarters without robust health care and hygiene infrastructure, says Perry—and a strain of influenza did affect asylum seekers in Mexico’s border region. But, she adda, “you have influenza in the United States, too. That’s not unique to refugee populations.” In Tamaulipas, where Global Response Management runs their clinic, 16 migrants and asylum seekers have tested positive for COVID-19, making up just 10 percent of the state’s 193 cases.

Oscar Ginera Aparicio, the state director of health services in Tijuana at the time of the interview, said that, historically, there has not been much basis for the fear of disease transmission between local and migrant populations. In fact, he said, as Central American migrants from the Northern Triangle countries of Honduras, Guatemala, and El Salvador began to pour into Tijuana, they were “more likely to get sick from conditions that we have here.”

In Tijuana, respiratory illnesses, diarrhea, allergies, and skin rashes emerged as the most common afflictions among the more than 6,000 Central Americans who entered the city in late 2018, said Ginera Aparicio. They didn’t have “the diseases that people thought they could have,” he said, naming Zika, dengue, and yellow fever, specifically. Initially, when the caravans first arrived, doctors running clinics at large makeshift shelters treated some 50 pregnant women. Five of the women gave birth in Tijuana. Doctors detected a few tuberculosis and HIV cases in people that for the most part were already in treatment. In later months, the shelters that have long housed migrants experienced limited outbreaks of some common illnesses like chicken pox and scabies among the newcomers. But none of this, Ginera Aparicio said, posed any danger of contagion. Follow-up calls and messages to Ginera Aparicio to get an update on the coronavirus situation in Mexico went unanswered.


What research does show is that migrant and refugee children often suffer from anxiety, depression, and post-traumatic stress disorder. As their numbers grow around the world, psychologists and other mental health professionals are increasingly searching for effective interventions. So last fall at Movimiento Juventud, Hernández drew on her knowledge and experience as a psychologist. Games and playful activities like coloring can help children learn to identify, understand, and manage their emotions, she said.

About a dozen elementary-aged children gathered around a table, where Hernández—who is no longer visiting the shelter and now works for a different organization—was pulling workshop materials from her tote bag. She distributed a drawing of empty jars, labeled with emotions—happiness, sadness, fear—and after explaining what the words mean, she invited the boys and girls to color their emotion for the day. They got busy, trying to figure out the right shade to express their feelings. “We explain the whole dynamic to minors who are just arriving and then we begin to see how they’re doing,” she says. “Many are confused. They don’t know why they’re here.”

In workshops and one-on-one sessions with adults, Hernández often witnessed their grieving over family separation and displacement. “There’s a lot of loss,” she says. “They have left behind their place of origin, their whole life there.” The workshops are designed to be of benefit at that moment, Hernández explains, acknowledging that assistance to migrants fluctuates because of the transitory nature of the population. “I can come in one day and the people who have participated are no longer here.”

Migrants who experience violence or other trauma before or while they are migrating are especially vulnerable to psychological distress. A 2017 study published in the scientific journal PLOS One found that among 234 migrants interviewed in McAllen, Texas, most cited violence as the main reason they’d left their homeland—and more than two-thirds had symptoms of post-traumatic stress disorder, depression, or both. “These findings suggest that the majority of Central American migrants arriving at the US border have significant mental health symptoms in response to violence and persecution, and warrant careful consideration for asylum status,” the study concluded.

In shelters throughout Tijuana, many migrants shared harrowing stories of violence and persecution. Migrant Sarai Miguel Herrera fled Guatemala with her daughter to escape an abusive husband. While traveling, the mother said, she was robbed. “I was always worried about my daughter, that she might be harmed,” Miguel Herrera recalls. During an initial appearance at a US immigration court, Miguel Herrera says, she had an emotional breakdown while recounting her reasons for leaving Guatemala.

At the shelter where Miguel Herrera was staying, Gina Celaya Torrez describes how her experience in a U.S. detention center left a deep mark on her psyche. Last summer, she and her 10-year-old daughter waded across the Rio Grande to illegally enter the US. They were subsequently detained by the U.S. Border Patrol and taken to a holding cell—or, as migrants say, “hielera,” the Spanish word for icebox. Along with dozens of other migrants, Celaya Torrez and her daughter slept on the concrete floor of a cold, foul-smelling holding cell with no access to private bathrooms. “We were like sardines in a can,” she recalls.

Children’s art papers the walls of the Movimiento Juventud 2000 migrant shelter.
Children’s art papers the walls of the Movimiento Juventud 2000 migrant shelter. Lourdes Medrano

Migrant advocates long have protested conditions that can affect the health of migrants in cells designed for short-term, not long-term detention. In the past year or so, at least three children have died of the flu while in detention, and cases of COVID-19 have been reported. For instance, at a migrant shelter in Chicago, at least 37 children have tested positive. And the U.S. Immigration and Customs Enforcement has more than 250 detainees under their custody with confirmed cases of COVID-19. Cold, overcrowded, and unsanitary is how the American Civil Liberties Union described the holding cells in a class-action suit filed in 2015 against the Department of Homeland Security, which oversees the U.S. Customs and Border Protection. On Feb. 19, a federal judge ruled that detention conditions violate the constitution, and ordered the agency to provide a medical assessment and basic necessities such as potable water, food, and a bed to migrants held longer than 48 hours.

“It was like a nightmare,” Celaya Torrez says of her time in detention. Now, she relies on her faith, unsure whether to continue with the asylum process or return to economic hardship in her home country, Honduras.

“These are people who have walked very long distances to get here,” says Hernández, “and they’ve been through a lot.”


Josue Vasquex rushed down a flight of stairs into the bustling community center at Espacio Migrante, a migrant shelter less than a half mile from Movimiento Juventud. The cultural center and migrant shelter where Vasquez and his family were staying opened after the caravans arrived in the city, but has also recently closed its doors to new arrivals in response to the COVID-19 pandemic. The facility—which according to a coordinator is still providing medical care and mental health services to migrants who were present when the COVID-19 crisis hit—is run by workers and volunteers from both sides of the border. As Vasquez sat down, the rich sounds of an acoustic guitar mixed with the Spanish words of children reading aloud with an adult volunteer. It was a book about children who travel.

a U.S. asylum seeker from Honduras, and his daughter
Josue Vasquez, a US asylum seeker from Honduras, and his daughter Yeimi outside Espacio Migrante, a migrant shelter in Tijuana. Lourdes Medrano

Vazquez was tense, out of breath, and oblivious to the noises around him. That afternoon, he was consumed by thoughts of his wife’s illness. She was almost out of medication and he had no money to buy her more. Without it, he said, her health could quickly decline. In Honduras, where the couple lived with their three children until July, Vazquez’s wife, Rosa, was diagnosed with thyroid cancer and had surgery.

“She has to have regular checkups and take medication for life,” Vasquez said. Back home, he had a stable job with medical benefits for his family, but he said violent threats from gangs forced him to uproot his sick wife and young children.

Vasquez was trying to scrape a living in Tijuana. But without legal documents that allow him to work in Mexico, he was struggling to find a job. Earlier in 2019, Mexico’s government had given out a limited number of humanitarian visas that authorized migrants to live and work in the country legally for up to a year. But the practice ended about the time the Mexican federal government—under intense pressure to avoid US tariffs—acquiesced to receiving the throngs of asylum seekers being returned to Mexico under the Migrant Protection Protocols. The agreement between the two countries did not include financial assistance from the US, but Mexico was to provide health care, jobs, and education for returned migrants. Along border cities, migrants and their advocates say those promises remain largely unfulfilled.

Just across the street from Espacio Migrante is an old building, where Tijuana’s newest migrants—from Cameroon—passed the time playing cards outside. They said they faced violence and persecution in their homeland because they belong to an English-speaking minority. They, too, are seeking asylum in the US.

“Things are not looking like they’re going to improve,” says Calderón Vargas, the Tijuana physician. “They’re either going to stay the same or they’re going to get worse.” That’s not good news for migrants like Katherine Padilla, the mother of the 4-year-old boy who experienced hives at Movimiento Juventud. Back in her tent, she gave the boy the antihistamine she’d received from the city’s medical staff. “I hope this will help,” she said. Since the two fled Nicaragua’s political turmoil, the mother said, her main concern has been keeping her son safe and healthy.