Government study into mysterious Havana syndrome halted over claims of participant coercion

What just happened? The mystery of the illness that afflicted American and Canadian diplomats in Cuba and elsewhere in the world is likely to remain unsolved. The National Institutes of Health (NIH) says it has stopped investigating the so-called Havana syndrome after it was found that people had been coerced into taking part in the research.

Some of the people who reported suffering from Havana syndrome previously claimed the CIA told them that taking part in the research was a prerequisite for receiving medical care, reports CNN.

The NIH said that an independent review concluded some level of coercion had taken place, violating its code of ethics. As such, it was halting the study "out of an abundance of caution." The CIA said in March that people were not required to participate in the study.

A CIA official said the agency takes "any claim of coercion, or perceived coercion, extremely seriously and fully cooperated with NIH's review of this matter, and have offered access to any information requested."

The institutes said in statements that "The NIH investigation found that regulatory and NIH policy requirements for informed consent were not met due to coercion, although not on the part of NIH researchers."

"Given the role of voluntary consent as a fundamental pillar of the ethical conduct of research, NIH has stopped the study out of an abundance of caution. In NIH's assessment, these investigative findings do not impact the conclusions of the study."

Reports state that in 2016, several US personnel, along with some Canadian government staff and their families, were repeatedly attacked by "an advanced sonic weapon" while stationed in Havana over several months. Chronic symptoms included balance issues, cognitive problems, insomnia, and headaches.

The original 21 events in Cuba were characterized as starting with strange grating noises coming from a specific direction. The Associated Press previously released a recording of the supposed sound, which you can listen to below. Cuban authorities claim the noise is just cicadas.

The State Department took the incidents so seriously that it issued a formal travel warning, pulled more than half its diplomatic staff from the island, and said it would not issue visas in Cuba until further notice.

More than 1,000 US government workers have reported similar symptoms while stationed around the world. In addition to claims of it being a sonic attack, energy weapons, poisoning, and other techniques have been blamed, with Russia often said to be the culprit. However, five US intelligence agencies that investigated the cases last year concluded that the likelihood of Havana syndrome being caused by energy attacks involving a foreign adversary is "very unlikely."

Two studies – one that examined the brains of those believed to have Havana syndrome and one that ran a series of medical tests – found no differences between those experiencing the symptoms and those who did not.

"Our goal was to conduct thorough, objective and reproducible evaluations to see if we could identify structural brain or biological differences in people who reported AHIs," said Leighton Chan, chief of rehabilitation medicine and acting chief scientific officer at the NIH Clinical Center.

"While we did not identify significant differences in participants with AHIs, it's important to acknowledge that these symptoms are very real, cause significant disruption in the lives of those affected and can be quite prolonged, disabling and difficult to treat."