The US military has been asked to help discover what is behind mysterious “sonic” health attacks on dozens of American diplomats that triggered a range of ailments that have left doctors baffled.

More than 30 US diplomats stationed in Cuba and China reported experiencing sensations ranging from dizziness and concussion, to cognitive problems that made it impossible for them to work. Cuba has denied any involvement in the incidents, that have further strained the relationship between the two countries.

Now, it has been reported the state department has turned to even more federal bodies, along with the US Navy, to try and solve what is behind the incidents. NBC News said experts at the National Institutes of Health (NIH), the Centres for Disease Control and Prevention (CDC), and the Office of Naval Research, have been asked to weigh in.

They were approached after a two-year effort by the FBI and the US intelligence community failed to resolve what was behind the incidents that led the state department to withdraw almost half its diplomats from Havana. At the same time, as many as 370 diplomats and their families serving in China have been tested amid concerns they could also have been affected after one person in the city of Guangzhou was confirmed to have the same symptoms as the Cuba cases.

Canada has also reported 13 cases of unexplained health problems at its Cuban embassy since early 2017.

“The safety and security of US personnel, their families, and US citizens abroad is and has always been the department of state’s top priority,” the state department said in a statement when asked by The Independent about the report the navy had been approached.

“As we continue to report, a government interagency investigation, involving medical, scientific, and technical experts across the US government and academia, is ongoing to determine the source and cause of these events.”

The US Navy failed to immediately respond to enquiries, as did the CDC and NIH.

Scientists at the University of Pennsylvania who tested more than 20 US diplomats, said they believed they had suffered something similar to concussion, but at the same time different. While it was initially believed sonic attacks were responsible for the ailments, the scientists now consider microwaves were probably behind what happened.

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Douglas Smith, director of the University of Pennsylvania’s Centre for Brain Injury and Repair, told CNN the diplomats probably suffered brain injuries of some type and that microwaves were considered the most likely cause.

“It’s almost like a concussion, but without a concussion – meaning that they look like individuals who have persistent concussion symptoms but have no history of head impact,” said Mr Smith. “Just like we have ways to prevent people from having a concussion, you could think of maybe protecting your brain from these energy sources.”

Earlier this month, doctors at the University of Miami who first treated the diplomats said they had suffered a range of neurological, cognitive and emotional symptoms, but believed they had not endured concussion.

“Objective testing showed evidence of a balance disorder that affects the inner ear and a unique pattern of cognitive and behavioural dysfunction,” Michael Hoffer, professor of otolaryngology and neurological surgery, wrote in a paper published in the journal Laryngoscope Investigative Otolaryngology.



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“This cluster of auditory and neurological symptoms, along with associated psychological issues, does not resemble more classic traumatic brain injury based on our team’s vast experience in this area.”

In October 2017, the Trump administration said it believed its diplomats in Cuba had been “attacked” and announced it was withdrawing more than half its personnel. Two years after a detente in relations following five decades of Cold War hostility, it curtailed visa processing and expelled 15 Cuban diplomats from Washington.

In testimony before Congress in September, Peter Bodde, coordinator of a special state department task force, said the CDC and NIH had been asked to help “identify and to understand the mechanism for the cause of the injuries, the motive behind these attacks, and the identity of the perpetrators”.



Cuba has continued to deny any involvement in the incidents and has said the US has failed to provide concrete evidence that anything actually happened.

“Until today, there has been no evidence to prove that something occurred in Cuba that could have damaged the health of several US diplomats,” Carlos Fernandez de Cossio, a spokesman for Cuba’s foreign ministry said this month, according to the Associated Press.