Since 2016, a number of U.S. diplomats and federal employees have reported symptoms of a mysterious illness, the so-called Havana Syndrome.
The list of symptoms include hearing loud sounds, nausea fatigue, and dizzying migraines, among others.
The cause of this mystery illness is a source of curiosity, but it remains unknown.
Last year the State Department commissioned a study by the National Academies of Sciences for researchers to investigate Havana Syndrome.
NPR’s Sarah McCammon spoke to Dr. David Relman, a Stanford professor who headed the investigation.
One possible cause their group came to was a form of microwave radiation that occurs in a pulsed or intermittent form.
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