The agency said that some other programs may be "adjusted" in the coming weeks, however.
The Cuban ambassador to Canada, Josefina Vidal, said in a statement that Havana considered Ottawa's decision "incomprehensible", given it would not help solve the mystery of the health incidents and would hurt bilateral relations.
Previously, the Canadian government declared the Havana embassy as an "unaccompanied post", so diplomats there could not be accompanied by their relatives.
Canada said in November it was considering all options regarding its embassy in Cuba after a 13th case was confirmed.
Unlike the US government, which calls the incidents "attacks" and has blamed the Cuban government for failing to protect its diplomats, the Canadian government said in the statement that it maintains "a positive and constructive relationship" with Cuba.
Until the case in November, there had not been a reported case since October 2017, "quite a considerable period of time", the official said.
The United States reduced embassy staffing in Cuba to a maximum of 18 from more than 50 after more than two dozen personnel developed unusual illnesses.
The new case brings to 14 the number of Canadians - alongside 25 Americans - who have reported unexplained symptoms from dizziness, fatigue, headaches, hearing and vision complications, to loss of balance, nausea and an inability to concentrate.
It's the latest development in an global mystery that has seen Canadian and USA diplomats in Havana hit with concussion-like symptoms, and which has left governments scrambling to find answers in what's being called "unprecedented and very hard incidents".
Canada's diplomatic staff in Cuba will drop to eight from 16, a Canadian government source said. Canadian government officials provided a briefing on the latest developments on condition of anonymity. The Cuban government has denied any involvement in the incidents.
"Over all, we have a multifaceted relationship with Cuba, which is very positive and continues", another official said.
The United States withdrew most of its non-essential diplomatic staff in September, 2017, but Canada did not.
Kimberly Breier, the current USA assistant secretary of state for the region, noted the latest confirmed Canadian injury in a tweet.
"Our thoughts are with all those affected from Canada and the U.S. We demand the Cuban government fulfill its obligation to protect foreign diplomats & their families", Breier tweeted.
Canadian authorities say they are getting good co-operation from the Cuban government, which is also frustrated by the incidents.
The Canadian government is continuing to investigate, but no cause has been identified.