Here we go with this again…
A Medical Mystery Grows as U.S. Consulate Workers in China Fall Ill – NY Times, 2018/06/06
A crisis over a mysterious ailment sickening American diplomats and their families — which began in Cuba and recently appeared in China — widened on Wednesday. The State Department evacuated at least two more Americans who fell ill in China after hearing strange noises, officials said.
The new illnesses in China come just weeks after American officials reported finding their first case in Guangzhou, where a consulate employee got sick after reporting disturbing noises.
The illnesses in China have broadened a medical mystery that started in 2016, when American Embassy employees and their family members began falling ill in Havana. In all, 24 of them were stricken with headaches, nausea, hearing loss, cognitive issues and other symptoms after saying they heard odd sounds. The issue has roiled relations with Cuba, which immediately fell under suspicion, and led the United States to expel Cuban diplomats.
This seems to be a growing phenomenon in Communist countries.