What’s Behind the Mysterious Illness of U.S. Diplomats and Spies?

Whatever’s causing it, all signs point to Moscow.

U.S. Marines stand outside the U.S. Embassy in Havana
U.S. Marines stand outside the U.S. Embassy in Havana
U.S. Marines stand outside the U.S. Embassy in Havana on Feb. 21, 2018. Adalberto Roque/AFP/via Getty Images

Beginning in 2016, U.S. diplomats and CIA officials posted abroad, including in Cuba and China, began falling ill with debilitating headaches, vertigo, memory loss, dizziness, and other troubling symptoms. The U.S. government vowed to get to the bottom of the matter, tasking top investigators and scientists to unearth what exactly was going on. 

Beginning in 2016, U.S. diplomats and CIA officials posted abroad, including in Cuba and China, began falling ill with debilitating headaches, vertigo, memory loss, dizziness, and other troubling symptoms. The U.S. government vowed to get to the bottom of the matter, tasking top investigators and scientists to unearth what exactly was going on. 

Now, nearly four years later, they still don’t have answers. But new developments in the mysterious cases have once again brought the issue to light—including new reports in the New York Times and GQ magazine. U.S. officials suspect that whatever is going on, it could be part of a coordinated attack from a U.S. adversary. 

It’s not clear yet what could have caused these symptoms. Theories range from microwave energy weapons to poisoning to mass hysteria. But one thing’s for sure: U.S. officials overseas have suffered debilitating symptoms, and some feel they’re not getting the help they need from the U.S. government. 

Here’s what we know so far. 


Do we know what’s causing this?

In a word, no. But officials and scientists are narrowing in on a few theories, including the use of microwave weapons. In 2018, a team of doctors published a report in the Journal of the American Medical Association that found the diplomats affected in Cuba had sustained brain injuries similar to those caused by concussion, but had no recent history of head trauma. 

The study’s lead author, Douglas H. Smith, the director of the Penn Center for Brain Injury and Repair at the Perelman School of Medicine, told the New York Times later that year that while there was skepticism at first, there was increasing suspicion that the diplomats’ brains had been affected by microwaves. 

The U.S. military has developed its own prototypes of directed energy weapons that can deliver nonlethal charges. But the U.S. military’s system is as big as a truck and takes hours to power up—a bit too conspicuous outside a diplomat’s apartment in Havana. 

During the Cold War, the Soviet Union bombarded the U.S. Embassy in Moscow with microwaves for decades, what came to be known as the Moscow signal. They weren’t mind-control devices but a way to activate listening bugs implanted in the walls of the embassy. 

“The Soviets, in the bad old days like the 1970s, were using a lot of high-energy devices to actually do technical collection operations. But it turned out that if you cranked them up too high, it would also have negative health impacts. My assumption was always that that’s probably some version of that is what’s going on in China, and Russia, and Cuba,” said Steven Hall, a former CIA station chief in Moscow, who retired from the agency in 2015. 

There are other theories: toxins, or even mass hysteria. Canadian diplomats based in Cuba also sustained mysterious brain injuries around the same time as their U.S. counterparts. A study commissioned by the Canadian government pointed to side effects of chemicals used in fumigation against mosquitoes, noting that the diplomats’ brain damage occurred in an area that is susceptible to neurotoxins. Others suspect a mass psychogenic illness, where people from a tight-knit group convince themselves that they have developed similar symptoms, what one professor described to Vanity Fair as a kind of “placebo effect in reverse.” But the authors of the 2018 report noted that some of the symptoms experienced by the diplomats could not have been feigned, and that cases of mass psychogenic illness tend to pass quickly. 

The best hope of an answer may lie with a study conducted by the National Academy of Sciences. Commissioned by the State Department last spring, the academy convened neurologists, experts in electrical engineering, toxicologists, and epidemiologists. 

The committee submitted its report to the State Department in early August, but it has not yet been released to lawmakers or the public. “It’s been extremely frustrating to me and my colleagues, in some ways disheartening, and certainly surprising,” said David Relman, the Stanford University medical professor who chaired the committee. 

Relman couldn’t share the report’s findings, but he said that the committee reviewed four possible explanations for the health effects and found one of them to be the most plausible. “But that’s not to say that necessarily that one mechanism explains everything,” he said. “Because, again, this was really complicated clinically. Lots of people, lots of places, spread out over time.”


When did this begin?

The mysterious illness first garnered public attention in 2017 when a cluster of U.S. officials stationed at the U.S. Embassy in Cuba reported that they had been experiencing hearing loss, dizziness, headaches, fatigue, cognitive issues, and difficulty sleeping. The next year, U.S. diplomats based in China developed symptoms that Secretary of State Mike Pompeo told lawmakers were “very similar and entirely consistent with the medical indications that have taken place to Americans working in Cuba.” 

But there is at least one other case that significantly predates the Cuba and China clusters. In 2013, an employee of the National Security Agency named Mike Beck filed a workers’ compensation claim with the Department of Labor claiming that exposure to microwaves while on a trip to a hostile country in 1996 may have caused him to develop Parkinson’s disease at the unusually young age of 46. The agency released a summary of a classified intelligence assessment that found that a country Beck went to was believed to have had a “high-powered microwave system weapon that may have the ability to weaken, intimidate, or kill an enemy over time and without leaving evidence.” The New York Times reported that people familiar with the assessment said that the country in question was Russia. (The Department of Labor rejected Beck’s claim.)


How has the government responded?

Retaliating against Cuba presented no difficulty, as the Trump administration was already looking to undo former President Barack Obama’s thaw with the island nation. Fifteen Cuban diplomats were expelled from Washington, and the State Department issued a travel warning for American citizens. (The Cuban government has repeatedly denied it had any involvement in the supposed attacks.) In China, the response was far more muted, as Trump was trying to secure a trade deal with Beijing. “They have hung us out to dry,” Mark Lenzi, one of the diplomats affected, told the New York Times

Pompeo called the suggestion that political considerations had shaped the administration’s response “patently false” in a press conference Wednesday.

It’s not just China. Marc Polymeropoulos, the CIA’s former deputy chief of operations for Europe and Eurasia, who suffered all the same symptoms after a stay in Moscow in 2017, told GQ about his experience after the agency refused to transfer him for treatment to the Walter Reed military hospital. 

“The U.S. government handled this very poorly,” he told Foreign Policy. “This is like the [National Football League] 15 years ago with [traumatic brain injury], putting their heads in the sand.” 


Who is behind this? 

Suspicion has fallen on the Kremlin, given Russia’s history of using microwave weapons against U.S. officials and its interest in keeping U.S. relations with China and Cuba on ice. Moscow has proved willing to pursue its enemies in the West and is reported to have offered Taliban militants bounties to kill U.S. soldiers in Afghanistan. Russia’s foreign ministry denies any connection to the incident in Cuba. 

Yet there are indications. According to GQ, a CIA investigation using cellphone location data found that individuals believed to work for the Russian security services were in the area at the time that U.S. officials in these countries first began experiencing symptoms. But according to the New York Times, senior U.S. officials want to see more evidence before pointing a finger at Moscow.

Amy Mackinnon is a national security and intelligence reporter at Foreign Policy. Twitter: @ak_mack

Robbie Gramer is a diplomacy and national security reporter at Foreign Policy. Twitter: @RobbieGramer

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