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Stay home. Do nothing. Save lives.

That might well end up being the story of how Canada conquered the terrible pandemic of 2020.

While Italy and other countries waited to act until cases were flooding hospitals, Canada has a chance to get out ahead of the COVID-19 crisis, according to the researchers who have been watching the coronavirus wreak deadly havoc around the world.

"We can't afford to wait until we see how bad it is," said Dr. David Fisman, a University of Toronto epidemiologist. "That just means that you've missed the boat."

But social distancing is one of the most challenging things many Canadians have ever been asked to do.

Up close, it's messy. As schools close and events are cancelled, it looks like a society in retreat.

But in fact, it's a society taking control of a situation — a country pulling together in a collective effort to head off disaster.

One Toronto critical care physician published an open letter Thursday warning that this is Canada's one brief chance to change the course of this epidemic.

Thanks for posting. I hope other <a href="https://twitter.com/hashtag/physicians?src=hash&ref_src=twsrc%5Etfw">#physicians</a> have sent something similar. This is no time for incrementalism. Politicians are inching us towards the degree of <a href="https://twitter.com/hashtag/SocialDistancing?src=hash&ref_src=twsrc%5Etfw">#SocialDistancing</a> required. To slow down the progress of <a href="https://twitter.com/hashtag/COVID19?src=hash&ref_src=twsrc%5Etfw">#COVID19</a> we all need to <a href="https://twitter.com/hashtag/ShutItDown?src=hash&ref_src=twsrc%5Etfw">#ShutItDown</a> now. <a href="https://t.co/9qoyXCQvt4">https://t.co/9qoyXCQvt4</a> —@drmwarner

"I simply want you to know that the COVID-19 situation is dire and may soon be completely out of control," wrote Dr. Michael Warner, the head of the ICU at the Michael Garron Hospital in Toronto.

He wrote a cri de coeur and sent it to 200 colleagues and his Twitter followers with the hope that it might reach people in time to make a difference.

"We have some time before the surge in patients hits Canada," he said. "At least one week or longer."

Warner said he wrote it while he still had the time.

"Two weeks from now I'm going to be too busy to do anything but work."

His message is blunt:

Avoid all close contact with people unless necessary.

Never shake hands.

Cancel/avoid all travel.

"The only hope to slow the virus is based on community behaviour — that's you, your neighbour, your family…everyone," he wrote.

"The current risk to the individual remains low, but the risk to society is immeasurable. I implore you to follow these recommendations to slow the spread of the virus.

"Begin social distancing NOW — do not wait for a politician to tell you it is necessary."

'We have to shut this down'

Fisman, of U of T's Dalla Lana School of Public Health, said he almost shed tears of relief when he heard that Ontario announced Thursday it was closing its schools for three weeks.

He got the news while visiting some colleagues in an ICU, dreading the impending crisis and the risks that his friends could soon be facing.

"I feel a great sense of relief that we're starting to get it," he said, adding that Canada might just be learning from the mistakes made by other countries. "If you wait until things are bad, you've waited too long."

"We have to really shut this down in order not to have our health care system collapse in the way we're seeing in other countries. The time to do this is now."

Fisman has been following the outbreak since early January, when the world first heard about a new coronavirus circulating in China. He calculates that the time to act is before critically ill patients start flooding hospitals.

He calculates the disease progression this way: It takes about five days (on average) from infection to first symptoms, and about seven more days for the infected person to get sick enough to see a doctor.

Add another three days at least before patients become critically ill and end up in the ICU.

Paramedics carry a hazardous medical waste box as patients lie on camping beds in one of the emergency structures that were set up to ease procedures at the Brescia hospital, northern Italy, on Thursday. (Luca Bruno/The Associated Press)

Italy learned the hard way, waiting for those first ICU cases before testing for the coronavirus and then shutting down the country. Now horrific stories about overwhelmed hospitals are shocking Canadians into action.

Warner said the stories coming out of Italy prompted his letter.

"Patients are dying. Resources are being rationed. Non-COVID patients with treatable disease are not getting treated," he said. "I'm not scared of disease and getting sick. I'm scared of not being able to help people."

'Hell demon of a virus'

Other lessons Canada still has time to learn: the coronavirus loves a crowd. Church groups, cruises, large medical conferences — all have seeded outbreaks.

"That's how this hell demon of a virus operates," said Fisman. "I think we have time because we're not in the soup yet."

Canada's cases are growing, but so far hospitals are not yet reporting large numbers of critically ill patients.

That's why the country is in the midst of a surreal and unprecedented experience of watching major sporting events cancelled, jury trials postponed, theatres postponing performances and social events disappearing from the calendar one by one.

"None of us has lived through a time like this," said Fisman, who said the closest comparison is probably the 1918 Spanish flu pandemic. And studies of that experience can also guide behaviour now.

Members of the Red Cross Motor Corps, all wearing masks against the further spread of the influenza epidemic, carry a patient on a stretcher into their ambulance, Saint Louis, Missouri, October 1918. (PhotoQuest/Getty Images)

One 2007 study comparing Spanish flu in two U.S. cities is suddenly getting wide circulation.

Philadelphia allowed a large parade to happen even though the city already had cases of the Spanish flu. St Louis imposed social distancing within three days of the first cases, dramatically reducing the city's death rate.

Is it all an over-reaction? That's something that will only be decided in hindsight.

"I think only retrospectively will we know if it was the right time, but I think we have to use science to guide us," said Warner. "We have enough science from China and Italy to inform us of what appropriate decisions to make."

If the social distancing experiment works, and Canada slows the viral spread, the experts say the skeptics might have the last laugh after all.

Fisman hopes the people who call this an over-reaction will be able to gloat in six months.

Because that will mean Canada successfully dodged the worst of the COVID-19 pandemic of 2020.

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