“But those forces or injury to the brain can be from physical forces that aren’t necessarily traumatic strikes or blows. For example, we know that a blast … can cause brain injury,” Marshall said.
“There are different forms of energy that can cause it. Infection can definitely cause it … I don’t have any evidence of that at all or any suggestion of that. But I’m just saying that there are multiple different causes.”
Even now after his assessments, Marshall said the cause remains a puzzle. “The only connection I have is that these patients were associated with a government posting in Havana.”
Global Affairs officials also say that a multi-agency investigation has not yet been able to pinpoint a cause. An examination of potential environmental factors at Havana properties occupied by the Canadians ruled out air or water as the cause.
Some of the diplomats and family members associated the onset of the symptoms with strange noises heard at the time, like grinding noises or the sound of warping metal. However experts aren’t convinced there is a link.
In the absence of clear causes, there’s been speculation the ailment might be mass hysteria or conversion disorder, where a person suffers symptoms that can’t be explained by a physical cause, sometimes triggered by stress. It was a theory most recently advanced in a Vanity Fair feature, titled, “The Real Story Behind the Havana Embassy Mystery.”
But Marshall disagrees. He has also treated patients with such disorders and that’s not what he saw in the Canadians.
“I’m less inclined to believe that. Having seen these patients, that was not my overall impression,” he said.
“I have actually seen a number of patients with conversion disorder, factitious disorder over the years. These patients I’m seeing don’t seem to be like that,” he said.
For starters, Marshall said that some of the Canadians experienced symptoms before they became aware of a broader problem, discounting the possibility that they were influenced by reports of illness among their colleagues.
“Before they even knew something was going on, they were describing some pretty remarkable symptoms that would be hard to explain as it being due to other causes, like social influence or fear, anxiety,” Marshall said.
The union representing foreign service workers has also pushed back against suggestions that the mass hysteria is the cause.
The Professional Association of Foreign Service Officers (PAFSO) wrote to Prime Minister Justin Trudeau and Foreign Affairs Minister Chrystia Freeland a year ago to flag “serious concern” about the government’s handling of the case.
In that letter, obtained by the Star, the association accused Global Affairs of downplaying the impact of the incidents on Canadian personnel, “even going so far as to question whether or not the issues our members were psychosomatic in nature.
“PAFSO consider that the collective hysteria hypothesis is not rigorous and impossible,” stated the letter, dated Jan. 22, 2018.
It said that “repeated suggestions that health issues are imagined or the ‘symptoms of extreme stress’” were only adding to the duress felt by diplomats and family members already struggling with health ailments.
In a statement to the Star earlier this month, Global Affairs said the cause of the health woes was still not known.
“We are investigating any and all possible causes, and we will continue to take the measures necessary to protect our diplomats and their families,” the department said.
“Canada has an evidence-based approach to addressing this situation, and our response is guided by the advice of medical experts and treating physicians. At the current time, the cause of these health problems remains unknown.”
The U.S. State Department is sticking by its claim that its personnel were deliberately targeted. To date, 26 Americans have been identified with “otherwise-unexplained medically confirmed symptoms and clinical findings” and the department isn’t ruling out that there may be more cases yet.
“Given the seeming exclusive focus on U.S. government personnel and their families in Havana, as well as the scope and duration of incidents, the department has categorized the events in Havana as attacks,” the department said in an email to the Star. “The investigation is ongoing to determine the source and cause of the health attacks.”
Marshall said that the Canadians affected by the health problems are improving, thanks to therapy and in some cases medication but cautioned that recovery from brain injuries can take time.
“Life is complicated and other factors affect your function. So if you ask too much of your brain, you may not recover as expected or if you’re asking it to function at high level, you can have other complications, like your mood can change if you can’t do what you need to do and symptoms can persist,” he said.
Meanwhile, Global Affairs refuses to comment on the fate of Canada’s embassy in Havana after a high-level visit by officials last month.
In December, the department revealed that medical testing had confirmed yet another diplomat who had served in Cuba was suffering health problems. That brought to 13 the number of confirmed cases, including dependants.
The discovery of another case prompted the federal government to send a high-level team to Havana to evaluate diplomatic operations in the country to ensure the protection of embassy staff.
But since that visit the department has been tight-lipped on the outcome of that visit or what, if any, changes were made to Canada’s diplomatic footprint in Cuba, despite repeated questions from the Star.
Bruce Campion-Smith is an Ottawa-based reporter covering national politics. Follow him on Twitter: @yowflier