(CNN) — US officials have issued a health alert in China after a US government employee stationed there reported “abnormal sensations of sound and pressure” that indicated a mild brain injury.
The US State Department is looking into whether the report is similar to incidents in Cuba in 2016 and 2017, an American official told CNN, in which so-called “sonic attacks” on diplomats and family members led to a reduction in staffing there.
The official who fell ill was assigned to the city of Guangzhou in southern China and reported a range of physical symptoms from late 2017 through to April 2018, the State Department said. The employee was sent back to the United States for assessment.
The US Embassy in Beijing learned on May 18 that the clinical findings of the evaluation matched that of a “mild traumatic brain injury,” an embassy spokeswoman told CNN.
A US Diplomatic official told CNN the State Department “is looking into whether this is a sonic attack, similar to what happened in Cuba.”
CNN has reached out to China’s Ministry of Foreign Affairs but has not yet received a response on this matter.
According to the alert issued by the US State Department on Wednesday, the cause of the injuries to the employee in China remains unknown, but officials were not aware of other similar symptoms among the diplomatic community in the country.
The spokeswoman at the US Embassy in Beijing told CNN the State Department was taking the incident “very seriously” and was working to determine the cause and impact of it.
“The Chinese government has assured us they are also investigating and taking appropriate measures,” the spokeswoman said.
The State Department said in its Wednesday statement that anyone who experienced “unusual acute auditory or sensory phenomena” while in China should move away from the source of the noise.
Comparisons with Cuba incidents
The alert immediately raised comparisons with a series of unexplained incidents in Cuba that led to the withdrawal of most US personnel from the embassy in Havana. The cause of those incidents, reported in late 2016 and early 2017, still remains a mystery.
At a congressional hearing in January, US officials detailed how personnel came to experience a variety of symptoms including sharp ear pain, headaches, ringing in one ear, vertigo, disorientation, attention issues and signs consistent with mild traumatic brain injury or concussion. In nearly all cases, the ailments were preceded by some sort of “acoustic element,” such as a “high-pitched beam of sound” or a “baffling sensation akin to driving with the windows partially open in a car.”
Cuban officials previously denied they had anything to do with the diplomats’ health problems and said the whole affair might be the result of mass hysteria.