In 2016, American and Canadian embassy workers in Havana, Cuba, began reporting sudden cases of chronic headaches, ringing in the ears, vertigo and nausea, among other symptoms of illness. From there, American diplomatic personnel have reported similar symptoms elsewhere around the world, though the illness was still known as “Havana Syndrome.”
U.S. troops, spies and diplomats have reported the symptoms in places like Colombia, Vietnam, and 94 other countries. No one could figure out what was happening to the afflicted personnel, but what they did know is their symptoms were remarkably similar to those caused by Soviet surveillance equipment during the Cold War. American and allied intelligence agencies began to suspect a new, secret spy weapon was being used.
One theory posited that the symptoms of Havana Syndrome were caused by directed radio frequency energy, a kind of radiation that includes microwaves. A panel of 19 experts from the National Academies of Sciences, Engineering and Medicine concluded that microwaves were the “most plausible” mechanism to explain what was happening. There is little evidence that microwaves were the source, the panel just made the conclusion based on reported symptoms.
Intelligence operatives believed the most likely source of the potential microwave weapon could have been Russia, as many of the CIA’s personnel afflicted by the illness were on their way to discuss counterintelligence operations against the Russians. U.S. officials suspected the Russian GRU, its military intelligence agency, was the most likely culprit if there was a culprit.
The GRU has been involved in most of Russia’s worldwide covert operations, including cyber attacks against Western infrastructure, U.S. election interference, and the 2014 annexation of the Crimean Peninsula by Russian forces. The CIA believed it was the only Russian agency that could pull off such an attack.
Another theory was that there was no weapon, but rather the Americans were experiencing psychosomatic reactions to external stress. Other doctors say the illnesses are cases of functional neurological disorders, which could be the result of stress or of other factors, including illnesses or injuries.
In March 2023, CIA Director Bill Burns announced some of the preliminary results of the CIA’s investigation into Havana Syndrome, calling it "one of the largest and most intensive investigations in the agency’s history.” Though hundreds claim to be afflicted by the disorder and its symptoms, the CIA says it was not caused by a mysterious superweapon held by a foreign power.
The CIA conducted its investigation alongside six other intelligence agencies, and found no evidence the hundreds of cases of reported Havana Syndrome were caused by a weaponized attack, knocking down the microwave weapon theory. Insiders say the agency believes what its people experience is real, but do not yet have an explanation for it. There is no evidence in favor of the weapon theory, and some evidence against it.
Since the panel from the National Academies of Sciences, Engineering and Medicine first looked at the symptoms, more cases have been reported and progress in the area has been increased. Doctors and intelligence officials now conclude that the symptoms did not fall into any discernible patterns.
If it’s not a directed energy weapon attack by a foreign power and no one is sure what the medical symptoms add up to, then what is causing the more than 1,500 reports of Havana Syndrome symptoms? No one is sure.
“While we have reached some significant interim findings, we are not done,” Burns said in a statement. “We will continue the mission to investigate these incidents and provide access to world-class care for those who need it.”