The CIA has completed an interim intelligence assessment which concludes most cases of Havana Syndrome are unfounded. In other words, they are not the result of a foreign government attack with some kind of directed energy weapon.

In a new intelligence assessment, the CIA has ruled out that the mysterious symptoms known as Havana Syndrome are the result of a sustained global campaign by a hostile power aimed at hundreds of American diplomats and spies, six people briefed on the matter tell NBC News.

In about two dozen cases, the agency can’t rule out foreign involvement, including many of the cases that originated at the U.S. embassy in Havana beginning in 2016. Another group of cases is considered unresolved. But in hundreds of other cases of possible symptoms, the agency has found plausible, alternate explanations, the sources said…

The idea that widespread brain injuries symptoms have been caused by Russia or another foreign power targeting Americans around the world, either to harm them or to collect intelligence, has been deemed unfounded, the sources said.

People who have experienced possible Havana Syndrome symptoms and have been briefed on the assessment have expressed deep disappointment, the sources said.

This is one of those situations where it’s difficult to evaluate how credible the CIA report is since we’re never going to see it or get any of the details. We basically just have to take the CIA’s word for it. The NY Times does have a bit more detail on the report’s conclusions:

A majority of the 1,000 cases reported to the government can be explained by environmental causes, undiagnosed medical conditions or stress, rather than a sustained global campaign by a foreign power, C.I.A. officials said, describing the interim findings of a comprehensive study…

C.I.A. officials said there was agreement within the intelligence community about the finding that the majority of Havana syndrome incidents were not the work of an adversarial power conducting a sustained campaign around the globe. Still, confidence in that assessment ranged from low to high across various intelligence agencies…

But late last year, officials said the C.I.A. had been unable to find any evidence that a directed energy device was responsible, neither intercepting communications from a foreign government that suggested the use of such a device or readings showing the presence of microwaves at the location of an incident.

The detail about a lack of microwaves near the scene of incidents suggests that maybe the CIA or the Pentagon were monitoring for microwaves and didn’t find them. I’m sure there’s much more to that story but again we’re not going to get the details anytime soon.

Given the CIA’s willingness to essentially dismiss most Havana Syndrome complaints it’s odd that some of the early cases in Havana that started all of this (and an unspecified number of other cases from Vienna and elsewhere) are still being examined. Matt Yglesias’ Substack published a story last year arguing that Havana Syndrome was not the result of a foreign attack. The author of that piece argued the initial reports were the easiest to debunk:

Per reporting in Vanity Fair, ProPublica and elsewhere, here’s what happened: in late December 2016, a 30-something CIA officer showed up at the embassy’s medical unit complaining of headaches and hearing loss, which he suggested might be related to strange, annoying sounds he and several neighbors had complained about hearing in their yards and homes. Within weeks, two more covert officers sought medical attention for similar symptoms, and so-called Patient Zero was diagnosed with a damaged inner ear by a military doctor in Miami. Upon his return to Cuba, he apparently began telling friends and colleagues about his suspicious malady, playing some a recording of the noise he was now convinced was emitted from the device that caused his injury. It was the screeching sound that many of them recognized, which quickly drove such a frenzy of rumors that Ambassador DeLaurentis called a meeting to inform everyone about the investigation into what was increasingly being seen as a sinister pattern of acoustic assaults, and asking them to come forward if they thought they’d also been targeted. Around 80 employees and family members did so, pushing confirmed cases of similar illness into the double digits. By that summer, reports began to leak that “sonic weapons” were believed to be behind the incidents…

In 2018, some officials began to coalesce around a convoluted theory that the incidents were still attacks by novel weapons, but emanated microwaves rather than sound waves and that the noises victims reported hearing were merely the “Frey effect,” an auditory phenomenon caused by microwave exposure that makes people perceive sounds that aren’t there. Meanwhile, around the same time, three separate investigations — one Cuban, one independent academic study, one by a scientific advisory panel working on behalf of the State Department — determined the recordings of the eerie sound made by affected patients to be mating crickets…

Several people leaked the audio to AP in 2017, and the outlet both confirmed that they all sounded similar and that multiple patients confirmed the clip indeed sounded like what they’d heard. After the first several cases, the State Department even played recordings while onboarding new employees so they’d know what to watch for. In short, the cricket noise drove a significant part of the reason that early cases were understood to be attacks, and why individuals came to seek medical attention. That all this played out while microwaves were frying brains in technical silence is very tough to believe.

That story concluded Havana Syndrome was really a “mass sociogenic illness.” For now, it sounds as if that’s what the CIA has concluded most of the cases are as well.