For years there have been complaints from US personnel stationed overseas that mysterious forces were being used to give them headaches, nausea, vertigo and other health issues. Once known as "Havana syndrome", it's now referred to as AHIs, the new acronym for Anomalous Health Incidents.
Intensive investigations of the issue have been conducted since the problem became apparent in personnel at the US Embassy in Havana, Cuba in 2016. Possibilities for the issue have included not only waves generated by unfriendly nations but also natural causes, such as the mating cries of the Indies short-tailed cricket. In 2020 experts speculated that health issues were caused by a directed, pulsed radio frequency energy device, perhaps a top-secret development by Russia or China.
A Newsweek article from Sept. 2021 made these remarks about the incidents:
"On August 24, Vice President Kamala Harris went on a trip to Hanoi, Vietnam, after delaying the visit over concerns around Havana syndrome. There was an instance of the syndrome reported in Hanoi that the Biden administration said targeted the U.S. official involved.
In August, at least two U.S. officials stationed in Berlin sought medical treatment after developing symptoms of Havana syndrome. They were the first cases reported in a NATO country that hosts U.S. troops and nuclear weapons.
The syndrome has also been recorded in Colombia, Kyrgyzstan, Russia, Uzbekistan, and Austria, a nation that holds a neutral stance.
In 2019, Havana syndrome was also reported in Washington, D.C., when a White House official said they were experiencing the symptoms while walking her dog in a Virginia suburb of the city.
In early 2018, U.S. diplomats in Guangzhou, China reported that an employee at the U.S. embassy in the city had been experiencing symptoms since late 2017.
One of the earliest cases involved a senior CIA officer who had flown to Cuba in secret to meet colleagues. In her room at the Hotel Nacional in Havana in August 2017, the officer awoke to a low humming noise and feeling of intense pressure in her head. When she returned to the CIA headquarters in the U.S. a few days later, the officer noticed she had poorer eyesight and a lack of balance, meaning she couldn't drive or read. The incident prompted then-Secretary of State Mike Pompeo to shut down the CIA's office in Havana."
It turns out that US personnel and their dependents that qualify will be awarded compensation from $100,000 to $200,000. Since there are personnel from different federal departments, State, Defense, etc. a major effort will be made to assure that those with similar problems will receive similar amounts regardless of their employer. All of this falls under the terms of the Federal Employee Compensation Act.
Scientific observers from outside the US government sphere are skeptical about AHIs. They say that in this case the health problem is "mass psychosis", examples of which include the Salem witch trials of 1692, a "June bug" outbreak in 1962 in a US clothing factory, and a bout of extreme laughter among thousands of students in Tanganyika also in 1962. There are many other examples internationally, most of which involve a disproportionate number of young females.
Update: After more years of investigation a number of US intelligence agencies have cast doubt on the theory that the health issues claimed by Havana Syndrome victims are caused by the Russians or any other country, based mostly on the physical evidence. No mention has been made of how much has been paid out to these victims.