'Havana Syndrome': What we know about the puzzling illness plaguing US officials since 2016

Editor's Note: This story was first published on 26 June 2021 and is being republished after an intelligence officer traveling in India this month with the CIA director reported symptoms consistent with the so-called Havana syndrome. The story has also been updated to show the new developments.A CIA officer who was traveling with agency director William Burns to India this month reported symptoms consistent with Havana syndrome, CNN and The New York Times reported on Monday. The victim, who was not identified, had to receive medical attention, CNN reported, citing unnamed sources.The circumstances of the incident are still being investigated, and officials have not yet determined whether the CIA officer was targeted because the officer was traveling with the director, William Burns, or for other reasons. If the incident was caused by an adversarial intelligence service, it may not have known the officer was traveling with Burns.OriginThe "Havana syndrome", initially unnamed, first surfaced in December, 2016, among officials who were part of the American and Canadian diplomatic missions to Havana, Cuba, in the wake of an apparent thaw in the US-Cuba relations. Its symptoms range from mild headaches to permanent brain damage and the mysterious illness since then has affected scores of diplomats, spies and their family members.With the cause of the "disease" yet to be discovered, the CIA and the Pentagon believe that the Havana syndrome is a deliberate act of aggression... "directed" at US targets.Now, following the Hanoi incident, former CIA operative Marc Polymeropoulos, himself a victim in Moscow in 2017, said, "It would seem to me that our adversaries are sending a clear message that they are not only able to get at our intelligence officers, diplomats and US military officers... This is a message that they can get at our senior VIPs," to Cipher Brief Open Source Report on Wednesday.Effects of Havana Syndrome

• Hearing harsh mechanical sounds and/or experiencing uncomfortable pressure
• Vertigo, vision problems, and difficulty concentrating
• Hearing loss
• Intense nausea and headaches
• Insomnia
• Brain damage
• Memory loss
• Cognitive difficulties

The theories

• Some researchers believe that ultrasound via intermodulation distortion caused by malfunctioning or improperly placed Cuban surveillance equipment could be a likely theory
• With so many officials complaining of hearing high-pitched ringing in their ears, initially it was believed that some kind of "acoustic weapon". But the US Air Force, after some experiments, concluded that any such effort using sound waves would be "unlikely" to succeed due to "basic physical principles."
• A 2018 study published in the journal Neural Computation by Beatrice Alexandra Golomb concluded that the syndrome was caused by pulsed radiofrequency/microwave radiation exposure.

Who is behind the attackWhile some officials in the Trump and Biden administrations believe Russian intelligence is responsible for the attacks, they have not yet found solid evidence.Government agencies have been stepping up warnings about the incidents in recent days, particularly for officials traveling abroad. Last week the Pentagon warned its entire workforce about anomalous health incidents, which it said often involve strange sounds or a sensation of heat or pressure followed by headache, nausea, vertigo and other symptoms.The new government warnings have all told officials that if they experience such sensations or symptoms to immediately leave the area they are in.Officials have struggled to determine the cause of the symptoms. While some officials are convinced they are attacks and that one or more rival powers are responsible, intelligence agencies have yet to come to any firm conclusions.Biden administration's takeUS president Joe Biden had made a rare public reference to the issue in a speech to intelligence officials in July earlier this year. He said the administration is "coordinating a government-wide effort to respond to these incidents, because this challenge demands that departments and agencies, including the entire intelligence community, work together with urgency."Reports of earlier incidentsEarlier in August US Vice President Kamala Harris is in Vietnam as part of a Southeast Asia trip where she is seeking to rally regional allies as the United States' superpower status takes a hit over Afghanistan.But her departure for Vietnam was delayed by several hours on Tuesday afternoon after her office was informed by the US embassy in Hanoi, Vietnam, of a "possible anomalous health incident", an apparent reference to the so-called "Havana syndrome", which has sickened diplomats in several countries.Again in June, US secretary of state Antony Blinken, said the United States is conducting a government-wide review to get to the bottom of who or what caused the suspected "directed" radio frequency attacks that on US diplomats that resulted in various neurological ailments known as "Havana syndrome".With inputs from agencies