Open this photo in gallery Beginning Wednesday, only four airports in the country – Toronto Pearson, Vancouver, Calgary and Montreal Trudeau – will be accepting international flights, Prime Minister Justin Trudeau said. Lars Hagberg/The Canadian Press

Canada will close its borders to people who are not Canadian citizens or permanent residents with the exception of U.S. citizens, diplomats and “essential workers” in an effort to stop the spread of the novel coronavirus, effective Wednesday, Prime Minister Justin Trudeau said Monday.

When asked about the science behind the government’s rationale, Mr. Trudeau said Ottawa recognizes the level of integration between the Canadian and U.S. economies puts the United States in a “separate category."

Mr. Trudeau’s announcement comes after a flurry of developments over the weekend including a warning from the federal government to Canadians to get home while the means to do so are still available and a stark message from Canada’s Chief Public Health Officer, Theresa Tam, that the window to stop the spread is narrowing.

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The Prime Minister, who himself is in self-isolation after his wife Sophie Grégoire Trudeau tested positive for the coronavirus last week, said Monday that airlines will receive a formal government order to ban all passengers who are presenting symptoms from getting on board.

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A basic assessment will be conducted based on advice from the Public Health Agency of Canada, Mr. Trudeau said, adding any individual with symptoms will not be able to enter the country.

Community transmission is now being seen in different locales, Health Minister Patty Hajdu acknowledged on Monday, adding that Canadians must take “extreme social measures” to stop the spread of COVID-19 as she warned that time is of the essence.

She said it is too early to tell if the steps that have been taken to date are stopping the spread, or slowing it, known as flattening the curve.

Beginning Wednesday, only four airports in the country – Toronto Pearson, Vancouver, Calgary and Montreal Trudeau – will be accepting international flights, Mr. Trudeau said.

"Let me be clear, if you are abroad, it is time for you to come home," he said.

Prime Minister Justin Trudeau outlined new international travel restrictions for Canada to counter the spread of the coronavirus. Canada will close its borders to non-citizens or permanent residents, with exceptions for key people, immediate family and U.S. citizens. Trudeau also urged Canadians abroad to come home. The Globe and Mail

Those who return to the country should self-isolate for 14 days, Mr. Trudeau said.

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At the moment, Canada is advising Canadians returning from outside the country to self-isolate for two weeks, but it is not mandatory despite calls from the federal Conservatives to take that step.

Enforcement measures would be required if the government took that approach, Mr. Trudeau said, adding the government is confident that Canadians will take the necessary steps.

Canadians should also try to stay home as much as possible, Mr. Trudeau said, adding this will help to protect individuals and those around them.

Public Safety Minister Bill Blair said Monday steps are being taken at airports to ensure social distancing is practised and spaces are disinfected.

People considered by the government to be “essential workers” who need to travel to the U.S. frequently, such as airline, train and marine vessel crews, truck drivers and those whose profession requires cross-border travel, will be exempted from the self-isolation requirement when they enter Canada.

American visitors will also be asked to self-isolate upon entering Canada, said Deputy Prime Minister Chrystia Freeland, suggesting this will likely be a deterrent.

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Chantal Desloges, a Toronto-based immigration lawyer, said the measures seemed as though they were put together hastily. For example, she said it isn’t clear how refugee claimants or people with student or work visas would be affected.

The spread of the novel coronavirus that causes COVID-19 continues, with more cases diagnosed in Canada. The Globe offers the dos and don'ts to help slow or stop the spread of the virus in your community.

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