What is this baffling condition reportedly affecting U.S. diplomats posted overseas? Since 2016, thousands have described unusual symptoms that initially sparked fears of an attack involving acoustic weapons. Yet years later, no medical proof has confirmed neurological damage, leaving the origin of what’s now known as Havana Syndrome shrouded in doubt.
The story began in 2016 and quickly captured attention within the U.S. government. Dubbed Havana Syndrome, the condition even inspired a documentary series questioning whether it stems from foreign espionage—or something far less tangible, like a shared psychological response.
The first reports emerged from the U.S. embassy in Havana, Cuba. Diplomats described strange sensations: ringing in the ears, headaches, intense pressure in the skull, and in more serious cases, vision issues, cognitive impairment, and memory loss. Many associated these episodes with sudden, loud noises, fueling concerns about a targeted attack on diplomatic personnel.
Soon, similar reports surfaced across the globe. Nearly 1,500 U.S. government employees in Europe, Asia, and Australia claimed to have experienced the same symptoms. Some officials floated the theory of sonic attacks, possibly involving acoustic or ultrasonic weapons deployed by foreign adversaries such as Russia or China.
What are the causes of the neurological symptoms and disorders experienced by thousands of American diplomats stationed around the world? © Linaimages, Shutterstock
The mystery still stands
Despite years of investigations by intelligence agencies, the State Department, the Defense Department, and medical specialists, the true cause of Havana Syndrome remains unknown.
Two major reports released in 2020—one by the National Academy of Sciences and another by the Journal of the American Medical Association—outlined four possible explanations. These ranged from directed radiofrequency energy (deemed the most plausible by the Academy), to chemical or infectious agents, and finally to psychological and social factors.
Still, extensive testing has failed to produce concrete evidence. Brain imaging and medical examinations have not revealed consistent injuries or biological markers. In early 2024, a study by the National Institutes of Health found no detectable brain damage on MRI scans and no abnormalities that could reliably explain the reported symptoms.
As a result, the mystery remains unsolved. A growing number of experts now favor a more ordinary explanation—one rooted in stress, heightened awareness, and psychological group dynamics rather than a hidden weapon or covert attack.
