Employee health professionals know all too well that confined, crowded conditions for unvaccinated people during influenza season increases the change of an outbreak.

Leading clinicians and public health officials are strongly questioning the U.S. Customs and Border Patrol’s (CBP) decision not to vaccinate migrants in detention facilities against flu and other infections. The CBP should at the very least immunize employees so they do not bring the virus in to detainees or acquire it, says Amy Behrman, MD, FACP, FACOEM, director of occupational medicine at the Hospital of the University of Pennsylvania in Philadelphia.

“It is unethical and dangerous for the people outside the facilities as well as being completely wrong and immoral for the people inside,” she tells Hospital Employee Health. “Absolutely they should immunize the employees for their own and their families’ protection, and to protect the individuals in the facilities.”

Close Confinement Causes Easy Transmission

Closely confining people who may be weak and malnourished from an arduous journey sets the stage for an outbreak if flu or other infectious agents are introduced by a new arrival or a facility employee.

“You could not design a more ideal circumstance for the transmission of respiratory viruses and intestinal pathogens because of the close, sustained person-to-person contact they have within an enclosed environment,” says William Schaffner, MD, a leading vaccine expert and professor of preventive medicine at Vanderbilt University.

A letter1 submitted to Congress by clinicians at Harvard University and Johns Hopkins hospital said autopsy results show that three children have died in U.S. custody in part because of influenza since December 2018.

“These children were aged two, six, and 16,” the clinician letter states. “These tragic deaths appear to represent more than half of child deaths in the last year in these immigration facilities, and to reflect a rate of influenza deaths substantially higher than that in the general population.”

In addition to influenza, the CDC recently reported that from Sept.1, 2018, to Aug. 22, 2019, there were 898 confirmed and probable cases of mumps in detained migrants.2

The CBP has issued a widely quoted statement that “due to the short-term nature of CBP holding and the complexities of operating vaccination programs, neither CBP nor its medical contractors administer vaccinations to those in our custody.”

There is some speculation that medical care and vaccinations may occur at a later stage of the immigration process, but that could not be confirmed as this report was filed. “They are not thinking in terms of the individual,” Schaffner says. “They are thinking administratively and bureaucratically. We know that immunity develops over 10 days to two weeks, so some of these children who are less than eight years old would require two doses of vaccine separated by a month.”

With flu season approaching, time is of the essence. “All of this is more poignant and pointed because we have had not only the illnesses described, but they have had children who have died of influenza,” he says. “What could be more motivating for them to initiate protection against influenza at the earliest possible moment?”

Indeed, the issue raises a moral and ethical imperative for providers and caregivers. “CBP actually keeps some people much longer than two or three days. If they are not committed to providing medical evaluations and preventive health services, that’s terribly unfortunate,” Schaffner says. “We as a society have, because of these policies, assumed responsibility for these individuals. They are now our responsibility.”

Several major infectious disease groups also issued a joint statement calling the inaction on immunizations “a violation of the most basic principles of public health and human rights.”3 The statement was issued by the presidents of the Infectious Disease Society of America, the Society for Healthcare Epidemiology of America, the Pediatric Infectious Diseases Society, the HIV Medicine Association, and the American Society of Tropical Medicine and Hygiene.

“The CBP’s decision to withhold vaccinations against seasonal influenza from migrants in border detention facilities … runs directly counter to the imperative that no individual should be harmed as a result of being detained, and that the community standard of medical care be available to persons in the custody of the U.S. government,” the joint statement read.

Since 2010, the CDC has recommended universal flu vaccination for those age six months and older. “In conditions of overcrowding, poor sanitation, and emotional stress involving vulnerable populations such as pregnant women and young children, choosing not to follow the CDC recommendations is particularly egregious,” according to the statement.


  1. Melinik J, Winickoff J, Sharfstein JM, et al. Letter to the Department of Health and Human Services. Aug. 1, 2019. Available at: https://bit.ly/2kqGPE0. Accessed Sept. 30, 2019.
  2. Leung J, Elson D, Sanders K, et al. Mumps in detention facilities that house detained migrants — United States, September 2018-August 2019. MMWR Morb Mortal Wkly Rep 2019;68:749-750.
  3. Sears C, Hardy WD, Babcock H, et al. Customs and Border Patrol’s flu vaccine policy breaches basic public health tenet. Aug. 21, 2019. Available at: https://bit.ly/2KYSF1l. Accessed Sept. 30, 2019.