An American agent accompanying CIA Director William Burns to India earlier this month has reportedly fallen sick with the so-called "Havana Syndrome".
Washington claims American spies and diplomats have in recent years been coming down with a mysterious illness, known as the "Havana Syndrome”, which disrupts the nervous system and causes a varying set of issues, including ear-popping, vertigo, pounding headaches, nausea and a "piercing directional noise".
The syndrome has allegedly struck some 200 US diplomats, spies and troops around the world, and has come to be known as "Havana Syndrome" after US diplomatic personnel in Cuba experienced similar occurrences in 2016.
The unnamed intelligence officer, who accompanied Burns during his visit to New Delhi, had complained of suffering from the "Havana Syndrome" symptoms, CNN and the New York Times reported on Monday.
A Central Intelligence Agency spokesperson said the CIA did not comment on such specific incidents.
“We have protocols in place for when individuals report possible anomalous health incidents that include receiving appropriate medical treatment,” the spokesperson told the news agency.
The incident marks the second time in less than a month that reported cases of the mysterious illness have impacted Biden administration officials during their travels abroad.
Last month, US Vice President Kamala Harris's visit to Vietnam was delayed when multiple American personnel reported symptoms consistent with the syndrome just ahead of her visit. At least two of them had to be medevaced.
Since 2016, the US has claimed that the mysterious illness affected a large number of American diplomats and spies in China, Germany, Austria, and the US itself.
About 100 CIA officers and family members are among some 200 US officials and kin sickened by "Havana Syndrome," Burns has said.
The CIA chief claimed that “there is a very strong possibility” the syndrome is “intentionally caused”, holding Russia responsible.
Last year, the US National Academies of Sciences, Engineering, and Medicine (NASEM) concluded that “directed, pulsed radio frequency energy” was the “most plausible” explanation behind it.
However, Cuban experts have dismissed the US claims. This month, a panel of Cuban scientists rejected Washington's claims of Americans overseas coming down with the "Havana Syndrome", saying the allegations are “not scientifically acceptable.”
The Cuban scientists said there was "no scientific evidence of attacks" of this nature on Cuban territory.
"We conclude that the narrative of the 'mysterious syndrome' is not scientifically acceptable in any of its components," the panel said in a report published on website Cubadebate.