TORONTO, Canada (AP) — Canada is considering all options regarding its embassy in Cuba after another diplomat was found to have fallen mysteriously ill.

A senior Canadian government official said yesterday that the latest diplomat affected first reported symptoms in the early part of the summer. Testing then confirmed it.

Canadian has confirmed 13 cases of mysterious health problems since early 2017. Twenty-six American embassy workers in Cuba have also been affected, suffering a range of symptoms and diagnoses including mild traumatic brain injury, also known as concussion.

The official said in a briefing for journalists yesterday that senior officials will visit Cuba next week and consider all options to ensure all staff are protected. They declined to specify what options they are considering. Canada currently has 12 Canadian staff at the Havana embassy.

Canada ordered the families of diplomatic staff in Cuba to return home last April. The 13 Canadians affected includes diplomats and some of their family members.

The Cuban government did not immediately respond to Canada’s statement but said in April after Canada pulled diplomats’ families that, “the Cuban government respects the decision adopted by the government of Canada but considers it lacking in justification, and reiterates that Cuba is a safe, stable and healthy country, for its inhabitants and for the almost 5 million foreigners who visit it every year, among them more than 1 million Canadians.

Cuba is a favourite tourist destination for Canadians, but the Canadian government said there is no evidence of any related ailments among Canadian travelers.

The Canadian official said Cuba has been co-operating from the beginning and said Cuba has expressed a desire to get to the bottom of the cause of these health conditions. Canadian government officials provided a briefing on the latest developments on condition of anonymity.

The mysterious case has sent US-Cuba relations plummeting from what had been a high point when the two countries, estranged for a half century, restored full diplomatic ties under President Barack Obama in 2015.