Open this photo in gallery A patient is taken into the emergency department at Toronto's Michael Garron Hospital by paramedics wearing protective personal equipment, Sunday, March 29, 2020. As of Sunday, there were more than 6,250 identified cases of COVID-19 in Canada and 63 deaths. Chris Young/The Canadian Press

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Canada is seeing a surge in COVID-19-related hospitalizations, intensive-care admissions and deaths, with the situation in Ontario, Quebec and Alberta posing the greatest concern, according to the country’s chief public-health officer.

On Sunday, Theresa Tam said the country is entering a critical period during which it will become clearer whether recent social-distancing measures are starting to slow the rate of new cases. While the number of COVID-19 cases is still expected to rise, experts will be watching the rate of infections and how quickly it is escalating in order to determine whether stricter measures are needed.

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This week “will be very, very important, for me anyways, looking at those trends,” Dr. Tam said during a briefing.

As of Sunday, there were more than 6,250 identified cases of COVID-19 in Canada and 63 deaths. According to the Public Health Agency of Canada, just under 7 per cent of people with COVID-19 in the country are hospitalized; 3 per cent become critically ill; and about 1 per cent die as a result of the infection.

Several provinces have seen a rapid escalation in severe cases in recent days. In Ontario, 72 people with COVID-19 were admitted to the ICU as of Friday, an increase of nine from the previous day. In Quebec, there were 192 COVID-19 hospitalizations as of Sunday, an increase of 28 from Saturday. A total of 72 patients there were in the ICU as a result of COVID-19 on Sunday, an increase of 15 from Saturday. In Alberta, 38 people were hospitalized as of Saturday, with 12 admitted to the ICU. A week ago, there were 18 hospitalizations in the province, with seven people in the ICU.

Dr. Tam said she’s concerned about those provinces in particular because all are seeing the spread of COVID-19 by local transmission. Data from the Public Health Agency of Canada show that 65 per cent of COVID-19 infections in Canada are linked to community transmission, meaning they have no link to international travel.

One critical-care physician said that if the current trajectory of new cases doesn’t change, Ontario’s health-care system will quickly run out of beds and ventilators, which are used to treat people who become critically ill as a result of COVID-19.

“The critical-care resources are finite,” said Michael Warner, medical director of critical care at Toronto’s Michael Garron Hospital. “We’re all in major trouble if this continues to stay ahead of us.”

Isaac Bogoch, an infectious diseases physician at Toronto General Hospital, said the next two weeks will be critical in determining whether social-distancing measures are having a positive impact. It takes roughly five to seven days for most people to develop COVID-19 symptoms and a few more days to get tested and receive results, so any new infections that occurred in the past two weeks will start to emerge now. Most parts of the country only started to shut down schools, restaurants, gyms and other public meeting places and to ban most gatherings about two weeks ago.

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“If we listened to what we are supposed to do, we’ll be okay,” Dr. Bogoch said. “If we didn’t listen ... and we facilitated transmission, going out and interacting with other people, then it’s going to be a lot more challenging.”

Dr. Bogoch said that because people have no immunity to COVID-19, social-distancing measures can only be relaxed once Canada dramatically reduces the number of cases and the rate of transmission. He expects that could take several months, at which point health officials will have to contain new cases and outbreaks by doing widespread testing and ensuring anyone who is infected remains isolated. That system will have to remain in place until a vaccine is developed, which will likely occur in a year to 18 months, he said.

Dr. Warner said he wants governments to be more forceful with messages about social distancing, as it’s one of the only tools available to slow the spread of infections, hospitalizations and deaths. He said health officials and government leaders should be more transparent about the fact social-distancing measures will likely need to be in place for at least a few months.

“Let’s be clear with people,” Dr. Warner said. “Let’s make people understand this is the new way of life for now. Let’s accept it and move forward.”

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