The man woke with a shock. A grating, screeching noise filled his head, all but deafening him. He sat bolt upright, surprised that his wife remained asleep amid the wrenching din. It was just after 3 on what should have been a quiet Thursday morning in Havana.

“That sound lasted 20 to 30 minutes, and I couldn’t find where it was coming from – then it faded, grew slower in pace and lower in frequency, and then I felt like I was going to throw up – I had the most overwhelming nausea,” the middle-aged Canadian official said in an interview this week. He got through it, dozed off briefly and then was awoken again when his wife entered the bedroom carrying their oldest child, who was covered in blood. At around the same time his father had been experiencing what he called the loud noises, the child had suffered a “massive” nose bleed – “there was blood everywhere in his room.”

It was the early morning of June 1, 2017. This family’s terrifying night was the first medically confirmed Canadian incident of what became known as the “Havana syndrome,” mysterious concussion-like brain injuries that had struck officials and intelligence agents at the U.S. embassy in Cuba – and, Ottawa realized that morning, was also causing serious injury to Canadian staff, their spouses and children.

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The story of the federal government’s response to the slow unfolding of a disturbing medical emergency at its Cuban embassy has largely been kept secret. Drawing on interviews with half the Canadian diplomats who were diagnosed in 2017 and with former embassy managers, correspondence between government officials and other documents, it is now possible to tell that story. What emerges is a confusing set of responses, some quick and empathetic and some slow and bureaucratic, emerging from government agencies and officials.

Because they are still government of Canada employees and not permitted to speak to the media, The Globe and Mail has allowed the diplomats and embassy staff to be quoted anonymously.

For two months before that June 1 incident, at least four families on the Canadian embassy staff had been reporting unusual health symptoms. The affected staff come from a wide range of embassy occupations, from technicians to people in politically sensitive senior positions; they were members of three different unions. The Canadians lived in housing provided by the federal government.

The man whose family reported the June 1 experience had known something else: On April 10, an American neighbour told him that staff at the U.S. embassy had suffered something they were calling “sonic attacks,” and were being evacuated to the United States.

He relayed this information to Canadian Ambassador Patrick Parisot, who had told him to keep it secret and not to share it with any colleagues or family members. Two weeks later, on April 23, Mr. Parisot was invited to the U.S. embassy, where he and ambassadors from a few other countries were told about the alleged attacks.

In mid-May, two Canadian families who reported symptoms in writing to the embassy were given authorization to travel for medical purposes to Canada, although it was not clear where they would be sent or when. All were told not to discuss the situation with family, friends or colleagues. A family’s request for a transfer of living quarters to another part of the city was declined.

At this point, federal officials appeared to doubt that the symptoms indicated brain injuries: A May 28 Global Affairs Canada e-mail obtained by The Canadian Press concluded that “many of the symptoms are similar to signs of extreme stress, and there is the possibility that there could be mental health effects caused by the fear of being targeted.”

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This was unfolding during a time of transition and upheaval in Cuba. November, 2016, had been a turning point: Only a year after the United States had reopened its embassy, which had been closed for 54 years, Donald Trump was elected President, pledging to roll back Barack Obama’s Cuba opening and restore economic sanctions. Eight days later, Prime Minister Justin Trudeau visited Cuba; 11 days after that, Fidel Castro died. That month, Cuba’s economy began a serious economic recession. The presidency of Raul Castro, Fidel’s brother, was drawing to a close, and that winter, Miguel Diaz-Canel, the secretive hardliner who was to replace him that April, was already reported to be pulling strings. Rumours of factional struggles beneath the surface were rife.

It was during that volatile November that Americans began experiencing deafening, disorienting “attacks.” When Canadians began reporting symptoms in April, the embassy did not associate them with the U.S. cases – in large part because their experience was different from what the Americans had characterized as sonic attacks. That all changed after the Canadian family’s June 1 incident.

When he went to work that day, the Canadian man was dizzy, and could not remember the security code he always used to enter the embassy – he could only push random buttons until an alarm went off and a guard let him in. He went upstairs and reported the incident to Mr. Parisot and his staff.

“His assistant thought I was drunk because I was staggering up the stairs,” the man remembers. “I don’t drink – never have.” His eldest child had never had nosebleeds. The other, uncharacteristically, had earlier started passing out in school. His wife had been experiencing a sudden spate of dizzy spells that prevented her from driving her motorcycle or performing calculations, although she had previously been in good health.

He spent the rest of the day “staring at the wall – I could not even look at a computer screen.” This time, the embassy moved fast. That Sunday, he and his family were rushed to the University of Miami, whose lab had tested the Americans. During nine days of tests, a neurologist diagnosed all four family members with “mild traumatic brain injury.”

That week, Mr. Parisot gathered the embassy’s management team and told them about the possibility that Canadians were being targeted. He told the managers to share the information with Canadian staff at their discretion; within seven to 10 days, all the embassy staff knew. (The Cubans employed by the embassy were not told until much later.)

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On June 12, the ambassador told the Canadian staff he had requested that Cuban authorities provide greater surveillance of the 17 homes used by Canadians. Staff were told to call the ambassador or senior staff if they experienced symptoms. They were also told they could call Cuban authorities, who would send a “SWAT-type team” of up to 30 people to investigate. On June 16, staff were told they should no longer call the Cubans, because, according to the diplomats, “one person had called and become the subject of an aggressive interrogation by Cuban authorities in the middle of the night, with children in the home.”

In July, 2017, the RCMP began an investigation. High-level meetings took place in Havana and Ottawa over the summer, involving staff from the Prime Minister’s Office, the RCMP, Global Affairs Canada, the Canadian Security Intelligence Service and other agencies. Little information was shared with embassy staff, who remained under instruction not to share what they knew with anyone.

A Health Canada doctor who had met with the medical team in Miami and had been briefed by U.S. embassy officials visited the embassy from June 18 to 22. He told staff that if they were experiencing symptoms, they could travel to the Department of National Defence in Ottawa for testing. During June and July, about nine embassy families were tested there.

In July, Global Affairs Canada began warning employees accepting postings in Cuba of the possible risk. Three families with young children were midway through moving and scheduled to arrive in August. They were assigned to the same houses in which affected staff had lived.

From July 11 to 15, a team of 11 RCMP officers travelled to Cuba, where they tested the 17 embassy-staff houses for traces of nuclear, chemical or biological weapons (they found nothing conclusive) and searched for radio-frequency activities, unusual audio or electronic signals. They ruled out naturally occurring phenomena. More RCMP visits followed in October and December.

At the end of August, the first Canadian family was repatriated to Canada. The reason was never explained to the other embassy staff – although the “Havana syndrome” story had broken in the media on Aug. 8, so most suspected. Two more families were instructed to leave in October.

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On Sept. 29, the Americans, with more than two dozen of their staff suffering injuries, decided to slash their Havana embassy staff by 60 per cent. The Canadian ambassador informed managers at a meeting that it would be “business as usual" at the embassy, and staff would not be reduced, because there was no reason to believe that Canadians were targeted.

On Oct. 13, eight affected employees sent the first of several letters to Global Affairs Canada’s deputy minister expressing concern about the lack of information and support for them. Three days later, a Global Affairs Canada counsellor arrived in Havana, and virtually all the embassy families booked appointments. The same week, Canada began giving its staff a baseline test known as HABIT (Havana brain-injury test) that the Americans had developed – a 30- to 40-minute procedure that assesses things such as balance, cognition and hearing for comparison with later testing. Adults received it in November and children in December – but diplomats say the tests could only be done in English, even though some staff and the majority of the children are francophone.

In December, 2017, lacking any system of comprehensive medical assessments and evaluation, some members of the staff asked the University of Pennsylvania’s Center for Brain Injury and Repair, which had become the lead assessment institution for U.S. diplomats affected by the “Havana syndrome,” if they could travel to Philadelphia to be assessed. In January, the UPenn experts told the Canadians that they were in contact with the Canadian government to see if this would be possible. In February, UPenn advised the Canadians that Global Affairs Canada had declined this offer.

In early March, a group of frustrated staff travelled to Pittsburgh for testing at their own initiative and cost (Global Affairs Canada later reimbursed them). The lab’s specialized MRI scans and other tests showed brain damage, and evidence of the similarity of the Canadians’ injuries to those of their U.S. counterparts was described by the chief neurologist as “rock solid.” However, no further testing was done in Pittsburgh – the Canadian staff say this was because Ottawa never provided UPenn with authorization.

“The unprecedented nature of these health impacts, together with the fact that no cause has yet been identified despite intensive efforts and an ongoing RCMP investigation, is frustrating and we understand it is extremely difficult for our affected staff and their families,” Global Affairs Canada spokesman Guillaume Bérubé said in an e-mail. “Their health and safety, together with that of our diplomats currently posted in Cuba, is our top priority.”

In the spring of 2018, Global Affairs Canada ended family postings to Cuba and withdrew all staff with families as more cases materialized (as of now, nine Canadian adults and four children have been diagnosed with the brain injuries). The Canadians who were affected in 2017 are all in Canada and still employed by Global Affairs, although several are unable to work because of their symptoms.

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