Beginning in late 2016, a mysterious illness befell U.S. diplomatic personnel and family members in Havana.
Specialists said the symptoms, described by those afflicted as “buzzing, grinding metal, piercing squeals and humming,” were similar to the brain dysfunction caused by concussions.
The U.S. government personnel in Cuba reported hearing these weird, loud sounds along with feelings of changes in air pressure in homes owned and maintained by the Cuban government and hotel rooms. Although there had been no history of head trauma, the symptoms reported were consistent with brain injury.
Some U.S. officials suspected the “health attacks” were intentional, perhaps perpetrated by the Cuban or Russian governments. But new research has implicated another culprit in the noise: Very loud crickets.
Scientists analyzed a recording of the sound reportedly related to the incidents released by The Associated Press in 2017 and found it matched the chirp of the Indies short-tailed cricket Anurogryllus celerinictus “in duration, pulse repetition rate, power spectrum, pulse rate stability, and oscillations per pulse.”
This particular kind of cricket is typically found in the Caymans, Florida Keys and Jamaica, but researchers Alexander L Stubbs of the University of California Berkeley, and Fernando Montealegre-Z of the University of Lincoln in England believe they may also be present in Cuba.
The researchers noted that the pulse structure of the AP recording initially didn’t match outdoor field recordings of the insects, but when the cricket call was played indoors, “the interaction of reflected sound pulses yields a sound virtually indistinguishable from the AP sample.”
They said their research, which has not yet been peer-reviewed, provides “strong evidence” that crickets produced the sound on the recording. However, their findings highlight the need for more rigorous research on what caused the diplomat’s ailments and does not rule out the possibility of another form of attack, according to the report.
The State Department created an expert panel to investigate the incident in July 2017 that determined the initial findings were most likely related to "neurotrauma from a non-natural source." The department recommended further investigation.
In response to the incidents in Cuba, the State Department expelled 15 Cuban diplomats from the Washington embassy and initially reduced the number of workers in Havana. These sharp reductions would later be made permanent due to health concerns. The State Department officials have told Congress that 26 embassy workers in Cuba were affected by the mysterious health incidents since it was first discovered in December 2016.
A team of specialists from the University of Pennsylvania’s Center for Brain Injury and Repair couldn’t determine the cause of the mysterious illness but found that the Havana patients “experienced persisting disability of a significant nature.”
The Cuban government insisted that it played no role in the attacks and worked with U.S. investigators to determine the cause of the ailments.
Contributing: Jessica Durando and Deirdre Shesgreen, USA TODAY
Follow N'dea Yancey-Bragg on Twitter: @NdeaYanceyBragg
This article originally appeared on USA TODAY: Remember that mysterious 'attack' on US diplomats in Cuba? Scientists think it was crickets