Instructions: In this task, you are given a text of many news articles seperated by special token "|||||". Your task is to summarize them.
Input: Eight Canadians posted to Cuba have experienced mysterious symptoms such as headaches, dizziness and nose bleeds in recent months, but Global Affairs officials say they are still at a loss to explain what is causing them. 
  
 The most recent incident affecting Canadian diplomats and members of their families took place in December. The person affected said they suddenly felt a wave of pressure. Symptoms reported by others have included headaches, dizziness, nose bleeds, loss of balance and sleeplessness. The symptoms reported by the Canadians have not been as severe as those reported by some Americans. 
  
 While one person affected continues to experience headaches, Canadian officials said Wednesday there is no indication following medical testing that anyone has experienced permanent damage. 
  
 Officials told reporters during a background briefing in Ottawa Wednesday they are in uncharted territory and have never seen anything like it anywhere else in the world. At this point, they said, they haven't ruled out anything, including foul play. 
  
 The mysterious ailments, which have triggered speculation worthy of a spy thriller, appear to only be hitting Canadian and American diplomats posted to Havana, Cuba. 
  
 U.S. media reported last year that U.S. authorities were investigating the possibility the diplomats and their families had been targeted by some kind of "sonic attack." However, The Associated Press on Monday cited a new FBI report that said the U.S. has found no evidence sonic waves were used. 
  
 U.S. officials told a congressional hearing Tuesday they are still working on several theories — including the possibility a virus was used. 
  
 Canadian officials said there have been no reports of similar symptoms among staff of other embassies or among Cubans. Nor have there been any reports of unusual symptoms among the thousands of Canadian tourists who visit Cuba every year. 
  
 The United States reduced the number of people posted to its embassy in response to the problems reported by 24 U.S. personnel and members of their families. 
  
 However, Canadian officials said they have no plans to reduce staff at its embassy. While a small number of diplomats and their families have opted to return to Canada, others have been sent to replace them after being fully briefed. 
  
 At the same time, the government has increased security measures around both the embassy and the residences of staff members. 
  
 Among the aspects officials have been studying are infrasound, ultrasound and environmental factors. While doctors have determined that some of the symptoms could be produced by auditory trauma, they said there is no known sonic weapon. 
  
 The U.S. government warns travellers to Cuba that embassy employees have been targeted by attacks and U.S citizens could be as well — particularly around the Hotel Nacional and Hotel Capri in Havana. The Canadian government is not planning to add a similar warning to its travel advisory. 
  
 While the officials did not say it, adding a warning to a travel advisory can have significant repercussions for businesses like insurance companies and airlines. 
  
 The first reported symptoms occurred in March 2017 but there was a cluster around May 2017 after the Canadian Embassy was approached by the American Embassy and it began to ask staff if they had experienced anything. 
  
 Overall, 27 staff members or their family members went through a medical examination and eight received further followup medical treatment. 
  
 The government is also doing baseline testing of those being posted to the embassy in Cuba, including those sent there temporarily, to allow them to determine if there are any future changes. 
  
 While a number of American staff said they heard a high-pitched sound before they began experiencing symptoms, only one Canadian reported that kind of sound. 
  
 The Canadians reported feeling the symptoms at their homes, rather than at the embassy. 
  
 Officials said Cuban officials appear to be as puzzled by the strange symptoms as the Canadians and Americans. ||||| Breaking News Emails Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings. 
  
 / Updated By Abigail Williams and Tracy Connor 
  
 It's not just the U.S. State Department that is baffled by the health problems of diplomats who've worked in Cuba. The Canadian government said Wednesday it also has no idea who or what is behind the mysterious ailments. 
  
 At a briefing in Ottawa, a Canadian official said eight of their citizens stationed in Havana, out of 27 tested, required medical care after reporting symptoms that ranged from dizziness and headaches to nosebleeds. Three diplomatic families left Cuba as a result, the official said. 
  
 The United States says 24 Americans affiliated with the embassy in Cuba have reported similar symptoms and signs consistent with traumatic brain injury. The State Department recalled all nonemergency personnel in late September and has no plans to return them, straining ties with Cuba. 
  
 Cuba has welcomed FBI agents to Havana to investigate. But officials told NBC News that the probe found no evidence of attacks. Additionally, some U.S. officials have questioned whether there's a single cause for the symptoms. 
  
 The State Department says the phenomenon is real. 
  
 "Is there any thought given to the fact that this is a case of mass hysteria? That a bunch of people are just being hypochondriacs and making it up?” Sen. Marco Rubio, R-Fla., asked during a Senate Foreign Relations subcommittee hearing on Tuesday. 
  
 "Twenty-four people have had symptoms and findings consistent with what looks like a mild traumatic brain injury. The objective tests that were done were not ones that could basically be easily faked,” State Department Medical Director Dr. Charles Rosenfarb testified. 
  
 "The findings suggest that this is not a case of mass hysteria," he said. 
  
 While officials in Washington initially theorized that the staffers and their family members were sickened by some kind of sonic attack, other possible culprits are under investigation. 
  
 "I think there’s viral, there’s ultrasound, there is a range of things that technical experts are looking at," Todd Brown, diplomatic security assistant director at the State Department, said during the hearing. 
  
 "When you say viral, you are talking about somebody intentionally implanting a virus?" Sen. Tom Udall, D-N.M., asked. 
  
 "That could be a possibility," Brown said. 
  
 Francisco Palmieri of the State Department told a Senate subcommittee it's "incomprehensible" that Cuba doesn't know who is behind alleged attacks that harmed U.S. and Canadian diplomats. KEVIN LAMARQUE / Reuters 
  
 Secretary of State Rex Tillerson has now decided to ratchet up the inquiry and convene an independent panel known as an Accountability Review Board. 
  
 At the hearing, Rubio grilled officials on why the board had not been set up earlier, in accordance with law. 
  
 "The law very clearly requires that within 60 days of an incident, and 120 days at most, that an accountability review board be stood up and they did not do that until almost a year after the first reports of the attacks,” Rubio told reporters. "That’s unacceptable." 
  
 The Cuban government has vociferously denied any involvement in or knowledge of attacks on American and Canadian diplomats. 
  
 "There is no evidence of any kind, not of the cause, not of the perpetrators, not of the origin, not of the motivations," a Cuban foreign ministry official, Josefina Vidal Ferreiro, said Tuesday evening. "There is no evidence at all, not one piece of evidence." 
  
 Despite the lack of evidence, the State Department said it's "incomprehensible" that leaders in Havana don't know what made the Americans and Canadians sick. 
  
 Rubio, an ardent critic of the island's Communist government, agreed. 
  
 "We can say we don't know how it happened, we can even say we can't know for sure who did it," he said. "But two things we know for sure: People were hurt, and the Cuban government knows who did it." |||||
Output:
Fresh off the news that an FBI report based on months of investigation found no evidence that sound waves could have damaged the health of American diplomats in Cuba, a new twist in the case: Canada on Wednesday said the inexplicable problems haven't let up. The CBC reports that eight Canadians have now suffered headaches, dizziness, and nose bleeds after time in Cuba, with the latest incident occurring just last month. In that case, the afflicted person reported feeling a "wave of pressure." Unlike the Americans, none of the affected have had lasting symptoms or damage. The CBC notes no other countries have reported similar incidents. NBC News reports that the eight Canadians needing medical care came from a pool of 27 who were tested. The US has found 24 Americans to have been mysteriously afflicted, and while the FBI report undermines the idea that a sonic weapon was used, other theories were discussed during a Senate hearing Tuesday. A State Department official said "there's viral, there's ultrasound, there is a range of things that technical experts are looking at." When asked by Sen. Tom Udall if viral meant someone "intentionally implanting a virus," the official answered that it was a possibility.