From late 2016 to August 2017, more than 20 American and Canadian diplomats on assignment in Cuba, as well as some of their family members, developed sometimes serious neurologic problems after hearing sounds of unknown origin, according to US authorities. Some of the observed symptoms mentioned by the US Department of State were hearing loss, vertigo, headaches, and cognitive, balance, and sleep problems. In late September of this year, the Department of State therefore decided to repatriate more than half of its Havana embassy staff, suspended the granting of routine US visas for Cuba, and called on all US nationals to avoid going to the island.
Since then, the patients’ symptoms and their possible causes have been closely examined, but the cause is still unknown. The authorities just revealed that abnormalities were observed in the white matter of the victims’ brains, although they did not indicate how many of the victims experienced these changes.
This new information, which was reported by Associated Press journalist Josh Lederman, shows that whatever the cause of the neurologic problems, physical injury to the brain had indeed occurred, according to US authorities.
Initially, most of the victims heard high-pitched metallic sounds and blaring noises and then experienced hearing loss or ringing in their ears, which raised suspicions of “acoustic attacks.” Some embassy staffers had also reported that sounds were audible in certain parts of rooms but were inaudible a few meters away, unlike normal sounds, which disperse in all directions.
The physicians therefore came up with the term “directional acoustic phenomena.” However, in the end, the sounds were apparently a consequence rather than the source of the attacks, according to three US agents, who wished to remain anonymous. Acoustic waves have never been associated with white matter damage, explained Elisa Konofagou, PhD, a biomedical engineer at Columbia University in New York City, who was interviewed by the journalist and who was not involved in the government investigation.
No Shocks or Explosions
According to the official communication earlier in the year, the patients suffered mild brain injury. The journalist pointed out that an association between brain injury and white matter changes was observed in the past in Iraq and Afghanistan war veterans who had survived explosions. Those changes were probably due to shock waves, but none of the Havana victims reported any explosions or blows to the head.
Physicians still do not understand what caused the symptoms and the white matter abnormalities or how these abnormalities might be associated with the observed neurologic symptoms. For the Cuban authorities, the US allegations are not scientifically plausible.
Outcome of the Symptoms
According to reporting from the Associated Press, most of the patients have experienced a full recovery, some after undergoing rehabilitation or other treatments. Many of them have reportedly returned to work. However, nearly one fourth of the patients had symptoms that persisted for long periods or are still unresolved.
In the end, physicians don’t know what the long-term medical consequences will be. The doctors from the University of Miami and the University of Pennsylvania who treated the Cuban embassy victims are currently writing an article in collaboration with the US Department of Health and Human Services and doctors working for the federal government. The article will probably be submitted to the Journal of the American Medical Association.
This article was originally published in the French edition of Medscape .
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