Havana syndrome

Havana syndrome is an alleged set of medical symptoms with unknown causes experienced mostly abroad by U.S. government officials and military personnel. The symptoms range in severity from pain and ringing in the ears to cognitive difficulties and were first reported in 2016 by U.S. and Canadian embassy staff in Havana, Cuba. Beginning in 2017, more people, including U.S. intelligence and military personnel and their families, reported having these symptoms in other places, such as China, New Delhi, India, Europe, and Washington, D.C. The cause and validity of the illness have yet to be determined.