Open this photo in gallery Police and private security maintain a quarantine due to coronavirus disease in the Tosh Jewish community of Boisbriand near Montreal, March 30, 2020. CHRISTINNE MUSCHI/Reuters

Montreal has emerged as Canada’s COVID-19 hot spot after an early spring break and close ties to New York and France sowed novel coronavirus infections that are rapidly growing into new cases and hospitalizations.

Montreal, with about 5 per cent of Canada’s population, has about one-quarter of the country’s COVID-19 cases, according to the latest data published by public health authorities. The province of Quebec, with 22 per cent of Canada’s population, has about half of the country’s cases.

Quebec had its biggest single-day increase Monday with 590 new cases, bringing the total to 3,430. However, the 19.6-per-cent three-day average growth in new cases is 6.4 percentage points lower than the previous three days, leading public health authorities to say they are optimistic the province’s rate of acceleration in new cases is slowing down.

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Hospitalizations and ICU stays for the sickest patients are also growing. Quebec had 235 COVID-19 patients in hospital Monday, an increase of 43. Among them, 78 were in the intensive care unit, an increase of six. By comparison, Ontario, with 72-per-cent greater population, had 72 patients in intensive care. Quebec has had 25 deaths, Ontario 23.

Public health officials and independent experts, along with Premier François Legault, point back to Feb. 28 to explain the province’s rapid expansion in coronavirus infection and serious illness. That was the last day of school before spring break for most Quebec school children.

As thousands of Quebeckers drove into the United States and flew to Europe and the Caribbean on holiday, the coronavirus was known mostly for infecting Asian countries, northern Italy, and a cruise ship off the coast of Japan.

While Quebeckers were away, on March 1, Florida declared a public health emergency. New York followed on March 7, as Quebeckers started to head home.

On March 11, when Quebec students had already been back at school for two days, the World Health Organization declared a global pandemic. On March 13, after four days of classes, the province closed schools and the federal government advised against non-essential travel outside Canada.

It is now about two weeks since the Quebec government enacted most of its stringent isolation measures. Fourteen days is also the longest time it usually takes for infected people to show symptoms.

“The number of cases will rise, but this week is crucial; this is when we’ll know if the measures are working,” said Nima Machouf, an epidemiologist at the University of Montreal. “The speed of increase will tell the story. If the increase is too rapid, it will mean we are not following instructions closely enough. If the curve starts to flatten, we will know we citizens have done our job.”

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Ontario might avoid Quebec’s rapid growth of infections because the pandemic declaration and more travel warnings came before spring break, which started two weeks later, but it is not certain.

“Most of the rest of Canada should count itself lucky it didn’t have a break from school to start March, when the United States wasn’t in a declared state of epidemic. They were in some ways saved,” Dr. Machouf said.

“On the other hand, other parts of Canada were slower to impose stringent measures. In a week we will also see what’s happening in other provinces. Hopefully they have been spared the worst.”

But, authorities stress, Quebec itself is far from out of danger. Cases have started to pop up in vulnerable populations. Federal officials said two Quebec penitentiary inmates and nine employees have tested positive at Port-Cartier Institution. The Montreal Gazette reported Monday one homeless man died in the city.

“We are seeing results from the measures we put in place but what we don’t want is for people to stop following instructions," said Horacio Arruda, Quebec’s Director of Public Health.

Officials quarantined a small Hasidic Jewish community north of Montreal, where officials reported at least 10 positive tests among 80 travellers recently returned from New York. “The community asked for this order to protect themselves as well as the surrounding towns,” said Eric Goyer, Director of Public Health for the Laurentians region. “They are co-operating fully.”

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Quebec says it has cleared 7,000 beds to receive COVID-19 patients. “We are in a situation that remains under control,” said Dr. Arruda.

Montreal public health declared a state of emergency and identified hot spots in neighbourhoods, including Côtes-des-Neiges, Notre-Dame-de-Grâce, Côte-Saint-Luc, Rosemont and Plateau Mont-Royal. In several cases, those are neighbourhoods with communities with close ties to New York, Florida and France. Public health officials instructed police to enforce the province’s ban on gatherings more closely in those areas.

Quebec has rapidly expanded testing and is now capturing milder cases that were not caught under stricter testing criteria a week ago.

In recent days, Quebec has averaged about 8,000 tests a day while Ontario has collected about 3,000 samples a day. Quebec has conducted about 808 tests per 100,000 people, more than double the rate of Ontario. Dr. Arruda said Quebec would rank fifth in the world for the rate of testing.

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