The Pentagon is hoping to get to the bottom of a mysterious illness dubbed “Havana syndrome” that’s been plaguing personnel since 2016. First reported by The New York Times, Defense Secretary Lloyd Austin issued a memo to all employees — service members, civilians, and contractors — urging them to look out for unusual symptoms of “Anomalous Health Incidents,” or AHI, on Sept. 15. Central Intelligence Agency director William Burns told NPR in July that it’s believed at least 200 Americans have been injured by the puzzling illness.
“As part of a government-wide effort,” Austin wrote in the one-page memo, “the Department is committed to finding the cause and source of these AHI and ensuring that affected individuals receive appropriate medical care as quickly as possible when needed.”
The memo describes “sudden and troubling sensory events” experienced by some DOD employees since the first cases of Havana Syndrome in 2016. Abrupt, unexplained headaches, pain, nausea, and vertigo are other symptoms the department encourages personnel to look out for and take seriously. Austin stressed that “each and every” report of these incidents will be investigated, and that employees who experience symptoms should immediately self-isolate.
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Havana Syndrome, the unofficial nickname for these unexplained and somewhat clustered incidents, first appeared in diplomats working at the U.S. embassy in Cuba in 2016. Subsequent cases have appeared, mostly among U.S. government officials and diplomats, in Asia and Europe. Michael Hoffer, the first medical professional to examine the embassy workers, has theorized along with other experts that workers may have been attacked by a “directed energy” weapon. Cold War-era surveillance equipment, according to The New York Times report, is also known to cause symptoms similar to those in reported cases. However, no definitive source or adversary has been deemed responsible.
“Your help and vigilance will help our efforts to fully understand the nature of these incidents,” Austin concluded as the government-wide investigation continues.