Medical Examiner

What Caused Cuba’s Sonic Attacks?

We still don’t know, but scientists are debating it within the pages of the JAMA.

The U.S. embassy in Havana with a classic vintage car out front.
American diplomats’ mysterious health problems inflamed tensions between the United States and Cuba.
Adalberto Roque/AFP/Getty Images

For the past year, scientists have been trying to understand what caused the mysterious “acoustic attacks” against U.S. diplomats in Cuba. Since late 2016, at least 26 people have experienced a litany of mysterious symptoms, including hearing problems, headaches, ear pain, dizziness, nausea, fatigue, and having trouble focusing, intense enough to land them in the hospital but with no recognized cause. In February, the Journal of the American Medical Association published a study by University of Pennsylvania researchers that attempted to understand what could have caused these symptoms. It didn’t deliver a conclusive answer, and now the same journal has published four letters by 10 scientists raising concerns about the first medical study’s accuracy. It’s just the latest chapter in what has already been a bizarre saga.

The February study in question found that the diplomatic personnel’s illnesses were not due to a covert “sonic device,” as the U.S. State Department had originally claimed. The researchers also ruled out poisoning and neurological illness caused by a tropical virus. Instead, the researchers concluded that the diplomats’ range of symptoms were consistent with concussions—except there hadn’t been any head trauma. Still, “if you didn’t know their history, they would look to you like other concussion patients,” Randel Swanson, the study’s lead author, told BuzzFeed News when the study was first published.

In the letters published on Tuesday, scientists noted that the original study improperly interpreted some cognitive test results and failed to conduct important tests on hearing and balance. Experts from the Ear and Balance Institute and Rutgers University’s Robert Wood Johnson Medical School took issue with this omission, since “a presumed sonic weapon attack would affect the inner ear more preferentially than any other part of the body, including the brain.” Presumably, this means an actual sonic attack might still be to blame.

Robert Bartholomew, a medical sociologist at Botany Downs Secondary College in New Zealand, also criticized the University of Pennsylvania team for discounting mass hysteria as a possible explanation for the ailments. Bartholomew, who is the co-author of several books on this subject, is one of the top figures that believes the diplomats’ mysterious symptoms were caused by a “mass psychogenic illness.” In his JAMA letter, Bartholomew wrote that researchers were too quick to dismiss a mass psychological outbreak as a viable possibility. Moreover, he points out that the February study did not have a “social network analysis,” which would have determined whether the affected diplomats knew each other or, at the very least, knew that other diplomats were ill—a key consideration in determining whether the sickness was a product of mass hysteria.

Several other researchers echoed Bartholomew’s concerns, writing that mass psychogenic illness should not be dismissed as made-up or “malingering”: “Although diagnostic caution is warranted, functional neurological disorders are common genuine disorders that can affect anyone, including hardworking diplomatic staff.”

Back in February, Frank Bures unpacked the science behind mass hysteria for Slate, arguing that humans have historically been susceptible to the phenomenon, even if we often fail to recognize it. In that article, Bartholomew noted that the conditions in Cuba were ripe for a case of mass hysteria: “This is a small, close-knit community in a foreign country that has a history of being hostile to the United States. That is a classic setup for an outbreak of mass psychogenic illness.”

But most people still don’t take this phenomenon that seriously. More from Slate:

Mass psychogenic illnesses are not as intuitive to grasp as cold or a flu, but they are just as serious, and should be treated as such. In Cuba, they have not been. Instead, a fixation on secret weapons has obscured a real illness with real consequences, one which can not only be “medically verified,” but which regularly afflicts people across the world, and to which anyone with a functioning brain is vulnerable. 

In a response accompanying the letters published by JAMA, the University of Pennsylvania team defended its research, calling the symptoms they observed “entirely different” from those seen in mass psychogenic illnesses. The FBI has agents in Cuba investigating the diplomats’ illness, and in July the Centers for Disease Control and Prevention also got involved. So far neither agency has come to conclusions on the matter.