US warns its citizens in China after embassy worker suffers brain injury from possible 'sonic attack'

REUTERS/Hyungwon Kang

The People's Republic of China flag and the U.S. Stars and Stripes fly along Pennsylvania Avenue near the U.S. Capitol in Washington during Chinese President Hu Jintao's state visit, January 18, 2011.

• A US State Department employee has suffered "subtle and vague, but abnormal, sensations of sound and pressure" that later lead to a diagnosis of "mild traumatic brain injury" while working in China.
• The strange trauma inflicted on the US official there recalls a similar spat of reports from Cuba, where US officials reported symptoms consistent with a "sonic attack" or exposure to harmful frequencies while abroad.
• It warned that if you experience any "unusual acute auditory or sensory phenomena accompanied by unusual sounds or piercing noises" to leave immediately.

A US State Department employee has suffered "subtle and vague, but abnormal, sensations of sound and pressure" that later lead to a diagnosis of "mild traumatic brain injury" while working in China - resulting in a warning to all US citizens there.

The strange truama inflicted on the US official there recalls a similar spat of reports from Cuba, where US officials reported symptoms consistent with a "sonic attack" or exposure to harmful frequencies while abroad.

"The U.S. government is taking these reports seriously and has informed its official staff in China of this event. We do not currently know what caused the reported symptoms and we are not aware of any similar situations in China, either inside or outside of the diplomatic community," the State Department warned in a health alert.

"While in China, if you experience any unusual acute auditory or sensory phenomena accompanied by unusual sounds or piercing noises, do not attempt to locate their source. Instead, move to a location where the sounds are not present," the State Department advises.

Emily Rauhala, the Washington Post's China correspondent reported that the State Department confirmed the embassy employee had been diagnosed with mild traumatic brain injury, which US officials in Cuba also experienced.

The Post reports that Chinese and US officials are looking into the matter. Previous victims of similar attacks in Cuba suffered permanent hearing loss, severe headaches, loss of balance, brain swelling, and disruption to cognitive functions.

The US originally called the Cuba incidents "sonic attacks," but later backed off that phrasing as medical experts examined the patients and found their symptoms and conditions of mysterious origins.

Medical testing revealed the embassy workers in Cuba developed changes to the white matter tracts that let different parts of the brain communicate, officials told the Associated Press.

But a purposeful attack hasn't been ruled out as the source of the brain injuries that have now struck US officials in two countries.

"The unique circumstances of these patients and the consistency of the clinical manifestations raised concern for a novel mechanism of a possible acquired brain injury from a directional exposure of undetermined etiology," a study about the victims in Cuba concluded.