Imagine hearing what sounds like marbles rolling around in a metal funnel. There's no marbles, and there's no funnel, but you can hear it with complete clarity, as if both objects were right next to you. This happens repeatedly over the course of several months, but you don’t say anything. How can you possible explain it? But there’s other symptoms too: headaches, sleeplessness, blurry vision, hearing loss, fatigue, nausea. Over time, it only gets worse.
This happened to two of the 170 employees in the American Consulate office and their wives between late 2017 and April of 2018 in Guangzhou, China, according to reporting from the New York Times. Both families were evacuated to the U.S. for further medical testing. It’s possible symptoms may be the result of a sonic attack, or else another inadvertent event, like the interference of eavesdropping devices.
Per an explainer by Lifehacker, it’s very possible for certain types of sounds to be weaponized. Infrasonic sound—or sound that comes in exceptionally low, deep tones—can cause symptoms that include “motion sickness, including ear pressure, headache, nausea, dizziness, [and] vertigo.” As noted by Seth Horowitz at Popular Science, low, powerful tones can carry a huge amount of pressure. This pressure can vibrate and rumble any liquid in your body, causing tissue to painfully expand and deflate.
Engineering researchers at the University of Michigan have argued that the culprit of the health crisis in Cuba is in fact ultrasonic sound, which is incredibly high-pitched noise. This type of noise can come from a super high-pitched whistle, or the interference of certain types of electronics, like eavesdropping devices.
“[Ultrasonic sound] may become harmful at large intensity or when in direct contact exposure to a vibrating source,” the University of Michigan researchers wrote. “In direct contact exposure rather than by air, ultrasound can cause thermal injuries.”
As noted by Lifehacker, ultrasonic weapons are extremely difficult to develop and deploy. (The U.S. military tried and failed in 2002 to find a practical way to create and implement such a weapon.)
This isn’t the first instance of this phenomenon for employees working in U.S. government consulates. Starting in 2016, American and Canadian diplomats, as well as tourists experienced similar symptoms in Cuba. The State Department accused the Cuban government of deliberately targeting twenty four U.S. diplomats and their families, which the Cuban government vehemently denied. Trump expelled fifteen Cuban diplomats from the U.S. earlier this year.
In the Guangzhou office, the Times reported that Mark Lenzi, one of the affected employees, worked for the International Republican Institute before his work for the American consulate, where he was involved promoting controversial democratic reforms in Ukraine and Georgia. (The Russian government strongly opposed this intervention.)
It’s possible that all of this has nothing to do with malicious foreign action. For instance, undetected toxins (like carbon monoxide, mercury, asbestos, and lead) can also cause these symptoms. Mass hysteria, a contagious psychological condition of partially or completely imagined symptoms, could also be responsible.
The U.S. is taking the possibility of a sonic attack extremely seriously. The acting director general and assistant secretary of state for diplomatic security were both promptly flown to the Guangzhou consulate after news of the medical crisis broke, and all the while, China and the U.S. are in the midst of an escalating trade dispute involving raising taxes on imported goods. However, it’s unclear when we’ll have answers on exactly what caused these waves of symptoms in the American Consulate in China and Cuba.