The Foreigner as Vector: America’s Most Durable Public Health Myth
This week, a Kenyan court suspended a plan negotiated in secret between the Trump administration and the Kenyan government. The plan: build a 50-bed facility at Laikipia Air Base — roughly 200 kilometers north of Nairobi — to quarantine Americans exposed to Ebola in the DRC, rather than fly them home.
Kenya’s doctors’ union called the country a “dumping ground.” The Law Society of Kenya pointed out the obvious: Secretary of State Marco Rubio had just told a Cabinet meeting that the United States “cannot and will not allow any cases of Ebola to enter the United States.” If America, a first-world country, won’t accept that risk, why should Kenya?
Rubio’s line is telling. It is not an epidemiological or a medically-grounded statement. It is a political one — and it is the same political statement that has driven American infectious disease policy toward foreigners, immigrants, and “outsider” populations for decades, from both parties. It is almost always wrong. It is almost always damaging. And it never seems to go away.
The country that built 13 Ebola centers and then refused to use them
After the 2014 West Africa Ebola outbreak, the United States created something remarkable: a network of 13 specialized Ebola treatment centers with high-level biocontainment capacity. These are facilities designed specifically for this scenario — a highly lethal virus, limited natural contagiousness, spread through direct contact with blood and body fluids. They are the right tool for exactly this moment.
Instead of using them, the administration flew Dr. Peter Stafford — a 39-year-old American surgeon and medical missionary who was infected with Bundibugyo Ebola in DRC while treating patients — to Charité University Hospital in Berlin, Germany. His wife, Dr. Rebekah Stafford, and their four children were evacuated there too for monitoring. A second missionary doctor potentially exposed, Dr. Patrick LaRochelle, was quarantined at Bulovka Hospital in Prague, Czech Republic.
Two American physicians. Eight family members. Four countries. Zero American Ebola treatment centers used.
On May 18, the CDC (acting director Jay Bhattacharya signing the order) invoked Title 42 of the Public Health Service Act to bar non-citizens who had been in DRC, Uganda, or South Sudan from entering the United States. Four days later, the administration extended this authority to cover green card holders — lawful permanent residents — something the COVID-era Title 42 did not do, something none of Trump’s prior travel bans had done.
This is not a public health measure. It is the same ancient reflex, dressed in modern legal architecture.
The 1987 original sin
We have been here before.
In 1987, Senator Jesse Helms successfully added HIV to the list of “dangerous contagious diseases” that rendered foreign nationals inadmissible to the United States. The scientific logic was essentially nonexistent: HIV is not transmitted through casual contact, it does not spread through air or water, and the mode of transmission (sex, needles, blood products) is identical regardless of a person’s country of origin. HIV was, for 22 years, the only disease explicitly named by Congress in the Immigration and Nationality Act as grounds for denying someone entry to the United States.
The policy did not slow HIV transmission within the US. The epidemic spread anyway — through American communities, American hospitals, American blood banks. What the ban did do: it stigmatized an already-stigmatized population, deterred disclosure and testing, and sent the message that this disease was something that came from outside, brought in by foreign others, rather than something that spreads wherever the conditions that enable it exist.
It took until 2009 — George W. Bush signing the repeal authority and Obama’s HHS formally removing HIV from the inadmissibility list — to correct a policy that was wrong from the moment it was written. Twenty-two years of political theater, dressed as public health.
Biden punished South Africa for being honest
Administrations of both parties have played this game. In November 2021, South Africa’s scientists did exactly what the global health community asks countries to do: they identified a new, potentially significant COVID-19 variant, sequenced it rapidly, and reported it immediately to the WHO. Within days, President Biden banned travel from South Africa and seven neighboring countries.
As I said at the time: “They discovered a new variant, they sequenced it, they let the world know. Shouldn’t you be praising them? What is the incentive for the next country that identifies the next important variant if their reward is what President Biden did to South Africa?”
Omicron had already been detected in Europe, Canada, Australia, and the UK before the ban was even announced. The ban didn’t prevent Omicron from arriving in the US — it arrived almost immediately. What it did accomplish was economic punishment for scientific transparency, and the establishment of a precedent that will make every future South Africa think twice before being forthcoming.
The International Health Regulations — the internationally agreed framework for pandemic response — do not recognize travel bans as an effective public health tool. That has not stopped governments from reaching for them every single time, because they are politically useful. They look decisive. They tell voters you are doing something to keep them out.
The current Ebola response is an object lesson in what this reflex costs
The 2026 DRC Ebola outbreak is caused by the Bundibugyo species — a rare variant that standard diagnostic tests initially missed. That diagnostic delay is the main reason this outbreak, which should have been caught in the 20-to-30-case range, reached over 1,000 suspected cases before the world got a clear picture of what was happening. The delay was likely compounded by USAID dismantlement and disarray at the RFK-controlled CDC.
The travel ban does not address any of these problems. It does not improve diagnostic capacity in DRC. It does not send resources to the outbreak zone — in fact, it makes it harder to get resources and personnel in, because it chills the willingness of healthcare workers to volunteer when their ability to return home is uncertain. My colleague Alex Phelan made exactly this point in The Guardian. The cascading effect on air travel to the entire region means that even countries not named in the ban face reduced access.
Meanwhile, the US has 13 world-class Ebola treatment centers sitting empty. Dr. Stafford was sent to Germany not because Germany has better biocontainment infrastructure — it doesn’t — but because “no Ebola cases on US soil” is a political goal shorn from any grounding in medicine or epidemiology.
RFK Jr. blames immigrants. Here’s what he’s evading.
At a House Energy and Commerce Committee hearing on April 21, 2026, Health Secretary RFK Jr. — facing questions about the ongoing measles outbreaks spreading across multiple US states — said this: “It has nothing to do with me. If you’re worried about polio and tuberculosis, you should look at the immigration policies in this country. ‘Cause the place where it’s occurring are the places where the immigrants are going, because they’re not vaccinated.”
This statement requires a specific kind of rebuttal, because it is not just factually wrong — it is the inversion of what actually happened.
The current US measles outbreaks are concentrated among unvaccinated American citizens. The Texas outbreak started in a Mennonite community. South Carolina. Utah among fundamentalist Latter-day Saints. Florida. These are not immigrant communities — they are communities where American parents, influenced by the anti-vaccine movement, declined to vaccinate their children. The Mexico measles outbreak was seeded from Texas, not the other way around.
But there is a more specific and damning story here. The most striking example of vaccine hesitancy in an immigrant community in recent US history is the Minnesota Somali community — which suffered a major measles outbreak in 2017 and again in 2024. MMR vaccination rates among Somali children in Hennepin County had fallen from over 90% before 2008 to just 35.6% by 2014. That didn’t happen spontaneously. It happened because anti-vaccine groups — including Robert F. Kennedy Jr. and Andrew Wakefield — specifically targeted the Somali community with the false autism-MMR link. They held meetings in the community. They distributed materials. They exploited an existing, understandable anxiety about autism rates in the Somali-American population.
RFK Jr. and his allies created the conditions for vaccine hesitancy in a specific immigrant community. Then he stood in front of Congress and blamed immigrants for vaccine-preventable disease outbreaks.
The audacity of that position deserves to be stated directly and clearly, because it is not just hypocrisy — it is a continuation of the same tactic. Point at the outsider. Direct attention away from the actual cause. Repeat.
Title 42 for measles and TB: theater, not science
Earlier this year, the Trump administration considered reinvoking Title 42 — the pandemic-era border expulsion tool — based on claims that migrants were driving measles and tuberculosis into the United States. In March 2025, immigration law expert Agustina Vergara Cid and I analyzed this in STAT News, and the conclusion was straightforward: there is no epidemiological basis for this claim.
The bulk of US tuberculosis cases occur in legal migrants from Asian countries, diagnosed decades after arrival — not in asylum seekers from the southern border. The 2024 Chicago measles outbreak linked to Venezuelan migrants at a shelter was real — but the entire Western Hemisphere had re-achieved measles elimination status by that point, and the actual vulnerability driving US measles spread is domestic vaccination refusal, not importation from the south.
Our threshold for when an infectious disease border declaration could be legitimately contemplated is: the disease must be severely serious, must lack simple countermeasures, and must pose an epidemiologically significant importation risk. Measles has a vaccine. Tuberculosis can be diagnosed and treated to render the person non-infectious. Neither condition came close to meeting that threshold.
As we wrote in STAT: “Title 42 did nothing to blunt the impact of Covid-19 either — like the current scenario, it was a brazen attempt to use a crisis to achieve a separate policy goal.”
The CDC should not be a tool for immigration enforcement. When it is, it loses the credibility it needs to do its actual job. That is the real cost of this reflex.
What actually determines whether a disease spreads
Here is the thing about infectious disease that gets lost in every iteration of this debate: the pathogen does not check passports.
What determines whether a disease spreads in a population is not the nationality of the person who carries it into the country. It is whether the population they encounter is vulnerable to it and the transmission characteristics of the pathogen (Ebola is very constrained in that regard depending on blood and body fluid emanating from symptomatic patients). That vulnerability is a function of vaccination (when available) rates, surveillance capacity, and the ability to identify and contain cases quickly. A community with 95% MMR vaccination coverage is inhospitable to measles regardless of who crosses its border. A community where MMR rates have been driven to 35% — by a deliberate disinformation campaign — is a tinderbox waiting for a spark, regardless of whether the spark is an unvaccinated American returning from Europe or an unvaccinated immigrant from a country with low coverage.
What changes is not the science. What changes is which outbreak politicians need to deflect accountability for.
The cost we keep paying
Every time the “foreigner as vector” reflex runs its course, it costs something real.
The HIV ban didn’t stop HIV. It delayed testing, delayed treatment, and drove infected people away from the healthcare system for 22 years.
Biden’s Omicron ban didn’t stop Omicron. It established that countries which report new variants honestly will be economically punished — a precedent that makes the world less transparent about the next one.
The Title 42 Ebola ban and green-card expansion is a political tool, not an outbreak management tool. The ban does not make us safer. We have thirteen cutting-edge unrivaled centers that can handle and have handled Ebola if an American healthcare worker is infected. What the ban will do is make it harder to get responders into the outbreak zone, harder to sustain the international cooperation that containment requires, and easier for an outbreak growing at 1,000+ suspected cases to escape the region entirely.
The Kenya facility — courts permitting — would have quarantined Americans in a country with no Ebola infrastructure rather than use the infrastructure we spent a decade building, all to satisfy a political calculus that says “no Ebola shall touch US soil.”
And RFK Jr.’s immigrant-blaming, delivered under oath to Congress, will go into the record as the official government explanation for why measles is spreading in communities that his own movement depopulated of vaccine confidence.
These are not separate stories. They are expressions of the same idea: that the disease comes from them, not from us. That if we can just keep them out, we will be safe.
It is an idea with a perfect record of failure and a perfect record of political utility. That combination is why it keeps coming back.
The answer is not to restrict the movement of people. The answer is to build the population resilience — vaccination coverage, surveillance, treatment access — that makes any pathogen’s arrival an inconvenience rather than a catastrophe. We know how to do that. We have the tools to master this problem. We keep choosing not to use them, and then looking for someone to blame when the outbreak comes anyway.