Information Note from the Embassy of Cuba in Canada

Following several investigations into alleged health incidents and symptoms reported by Government of Canada officials, Global Affairs Canada (GAC) informed that the  Interdepartmental Task Force determined that there is no evidence to attribute the symptoms experienced by Canadian-based staff members and their dependents in Havana, Cuba, to a foreign agent or foreign agents.

https://www.international.gc.ca/transparency-transparence/unexplained-havana-incidents-inexpliques-la-havane.aspx?lang=eng