The sweltering heat and suffocating humidity that have blanketed Eastern and Central Canada have contributed to the deaths of at least 18 people in Quebec over the last few days, health officials said Wednesday.

And with the muggy temperatures expected to persist for at least another two days, authorities are urging people to remain vigilant.

Montreal health officials said there have been 12 heat-related deaths since the weekend, while authorities in the Eastern Townships region east of Montreal are attributing another five deaths to the weather. Health officials for the Mauricie and Quebec regions have also confirmed at least one death.

Dr. Mélissa Généreux, head of public health in the Eastern Townships, told a news conference the victims are all adults — either seniors or people suffering from chronic illness. The deaths were not concentrated in any specific municipality.

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“There are still two days left of particularly hot weather with particularly high humidex levels,” Généreux said. “We’re inviting the population to be vigilant for the next two days — for themselves as well as those close to them.”

Officials across the province advised people to drink plenty of water and check in on neighbours or relatives and, if need be, get them to a place where air conditioning is available.

“It could save a life,” Généreux said. Tweet This

Environment Canada says a heat warning remains in effect for an area spanning southwestern and northeastern Ontario through southern Quebec and into the Atlantic region, with above normal temperatures and humid conditions likely to stick around into Thursday.

Dr. David Kaiser, physician-manager at Montreal’s public health authority, said officials aren’t surprised by the number of deaths in the metropolis.

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“We would prefer having no deaths related to heat but with four days of intense heat and especially hot nights, we expect to see an impact on people’s health,” Kaiser said.

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He said the Montreal heat exposure victims were between 50 and 80.

“None of the people we’ve identified in the last four days had air conditioning at home,” Kaiser noted. Tweet This

Prime Minister Justin Trudeau tweeted condolences to the relatives of the Quebec victims.

My thoughts are with the loved ones of those who have died in Quebec during this heat wave. The record temperatures are expected to continue in central & eastern Canada, so make sure you know how to protect yourself & your family: https://t.co/JSPPsU80x9 — Justin Trudeau (@JustinTrudeau) July 4, 2018

No deaths have been reported in other provinces. In Ontario, a spokeswoman for the coroner’s office said it couldn’t confirm if there were any heat-related deaths, adding it could take weeks or several months to complete such probes.

Kaiser said one reason Quebec has been reporting so many deaths is because it’s part of the province’s extreme heat plan, where health officials work in tandem with first responders and emergency rooms to track down potential cases of heat-related illnesses and deaths.

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“We go out to the paramedics, we go out to the hospitals and we ask them to make sure to identify any deaths they believe are related to heat and that allows us to intervene more quickly,” Kaiser said.

He cited a case in recent days in which a death in a home for the elderly led authorities to move five other people deemed at risk to a facility equipped with air conditioning.

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Police and firefighters also continued to go door to door in areas identified as having people considered at high risk: those with chronic illness or mental-health problems, those who live alone and people without air conditioning at home.

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Also on Wednesday, the ambulance service that serves a large swath of the Montreal area called on people to refrain from calling unless it is a real emergency.

Urgences-santé said it has been inundated by the volume of calls — 1,200 calls per day in Montreal and nearby Laval over the past four days, which is 30 per cent more than usual on busy days.