Artwork by Alex Castro / The Verge
Following weeks of speculation, clinicians have released the inaugural comprehensive analysis detailing the enigmatic medical condition that struck American diplomatic personnel posted in Cuba. Although the precise trigger remains unidentified, the researchers express strong confidence that acoustic weaponry was not responsible.
A team of specialists assessed 21 individuals connected to the American embassy in Havana, discovering that their clinical presentation mirrored those associated with traumatic brain injury—ranging from head pain and disrupted sleep patterns to emotional instability. Strikingly, however, no participants displayed clear evidence of cranial trauma, as outlined in a study appearing today in the Journal of the American Medical Association.
"It's essentially a concussion in the absence of trauma," remarks Douglas Smith, who leads the University of Pennsylvania's Center for Brain Injury and Repair and co-authored the study, during a podcast discussion. Smith and his fellow researchers hypothesize that the condition affecting the embassy personnel could represent a previously unidentified syndrome, potentially triggered by a common environmental factor present in Havana. Nevertheless, independent experts caution against drawing premature inferences, emphasizing the numerous unresolved questions surrounding the case.
From 2016 onward, American diplomatic staff in Cuba started reporting a peculiar cluster of health complaints—dizziness, queasiness, and auditory impairment. With a single exception, every affected individual recounted experiencing the initial onset of symptoms after detecting odd acoustic phenomena or sensing unusual pressure or vibrations within their residences or accommodations. These accounts fueled concerns that embassy personnel were victims of deliberate "health assaults," though FBI investigators failed to substantiate such claims. (According to a report from ProPublica today, a biologist consulted by US officials matched the unusual sounds to insect vocalizations.)
As autumn 2017 arrived, screening had been conducted on 80 embassy-affiliated individuals displaying comparable complaints, with the affected count rising to 24. Specialists at the University of Pennsylvania's Center for Brain Injury and Repair examined 21 of these cases, determining that the majority suffered from persistent headaches and insomnia. Numerous patients also struggled with cognition, attention, and visual tracking—issues that intensified following physical exertion. Three individuals experienced profound auditory damage. Standard neuroimaging yielded no abnormal findings. However, approximately twelve months afterward, merely seven of the 21 examined patients had resumed full-time employment, based on a JAMA news release.
The research team notes that no established mechanism exists by which sound alone could produce such a severe constellation of clinical effects. They propose instead that the unusual auditory experiences patients described likely represented a secondary effect of whatever truly injured them—comparable to the report of a firearm discharge. The investigators also dismiss infectious agents, toxic substances, and collective psychogenic responses as plausible explanations. "The most straightforward interpretation is that something genuine is occurring," stated one researcher during the podcast.
Conversely, certain specialists remain hesitant to exclude the possibility of socially transmitted mass psychogenic illness. An accompanying editorial highlights that the analysis fails to specify whether individuals whose symptoms emerged at later stages were aware of previously documented complaints—knowledge that could have heightened their own awareness of similar issues. Furthermore, the evaluating clinicians were aware of their subjects' identities, introducing potential bias into the assessment process.
Nonetheless, the current publication advances efforts to establish clinical benchmarks essential for identifying additional patients exhibiting comparable manifestations. "This constitutes a genuine public health concern, and we must remain vigilant about the possibility that additional affected individuals may exist who have not yet been identified," one investigator commented. "The medical community needs to be ready, and I would characterize our findings as merely an initial step."
