News that Toronto has its first suspected case of coronavirus may come as a shock to Canadians, but health officials have been preparing for this exact scenario for weeks.

"We knew that there was going to be a case in Canada. We knew that there was probably going to be a case in Toronto," Dr. Allison McGeer, an infectious diseases specialist at Mount Sinai Hospital in Toronto, told CBC News.

"It was just a question of time."

The unidentified patient is a man in his 50s who was taken to Toronto's Sunnybrook Health Sciences Centre with symptoms after travelling from the Chinese city of Wuhan to Guangzhou and then to Toronto on Wednesday.

Officials said he had limited external contact with people in Toronto when he arrived at his residence, before being taken by paramedics to hospital in stable condition.

"No one would be surprised if this is a positive case," said Dr. Isaac Bogoch, an infectious disease physician at Toronto General Hospital.

"It appears that this may have arrived on our doorstep and we're ready."

How concerned should the general public be?

McGeer, who contracted SARS in 2003 while working as a physician on the front lines of the epidemic, says she believes the risk to the public with this case is low.

"I'm not concerned about transmission from this case at all in Toronto," she said, adding that Toronto Public Health officials have already begun the process of contacting people who may have come in contact with the patient.

"There are mechanisms for making sure that we can get in touch with all of those people and as long as they're followed up, the rest of us who live in the city are not at any risk at all."

McGeer said there's still no indication that this coronavirus can be transmitted to anyone but people who have come in close contact with infected individuals, but officials will take precautions.

There are two types of transmission with a coronavirus like this: limited and sustained.

Limited human-to-human transmission occurs when there is close contact between those who have the virus and those who don't, particularly with family members, but is usually contained to a small number of people before running its course.

Health officials announce Canada's first 'presumptive' positive case of coronavirus is being treated in Toronto on Saturday. (Chris Young/The Canadian Press)

Sustained transmission is characterized by the World Health Organization as an illness that can transmit easily from one person to others in the population.

"It is now clear from the latest information that there is at least some human-to-human transmission," the World Health Organization in China said in a statement Monday.

"In addition, information about newly reported infections suggests there may now be sustained human-to-human transmission. However, we still need more analysis of the epidemiological data to understand the full extent of human-to-human transmission."

Ontario's associate chief medical officer of health Dr. Barbara Yaffe said at a news conference Saturday that officials would be looking to identify passengers on the flight the patient took to Toronto who were within three rows for potential risk.

Bogoch said that while the suspected case is not unexpected, by no means does it indicate that there is a wider outbreak in Toronto.

"I think that people should just go about their lives as they normally do," he said. "But also be aware of the news and follow the situation closely as things change."

How are health officials handling the situation?

Canada has already ruled out several suspected cases of the coronavirus in Quebec and Bogoch said that is an indication that the systems in place are working.

"Thankfully, those weren't cases, but at least it demonstrated that people knew what to do and where to go if they had symptoms suggestive of infection with this coronavirus," he said. "It almost was a bit of a test of the system."

Dr. Jerome Leis, medical director for infection prevention control at Sunnybrook Hospital, said the patient was immediately isolated for further investigation, placed in a negative pressure room with protective equipment and was in stable condition.

Watch: How officials are dealing with public fear over coronavirus

The patient in Canada presumed to have the coronavirus showed symptoms of the coronavirus while on a plane travelling from China to Toronto. The number of infections worldwide has surpassed 1,900 cases. 2:24

Bogoch said the work is not just being done inside the hospital, but preventing further transmission in the community and beyond.

"This is one case, this is still an evolving situation and of course we might get additional cases as well," he said.

"But we are prepared and the system appears to be working."

How does this compare to SARS?

We still don't know how dangerous the new virus is or how it compares to SARS, which had a case fatality rate around 10 per cent, or MERS, with an estimated fatality rate as high as 30 per cent.

"We are in a very, very different place than when we were responding to SARS," said Dr. Peter Donnelly, president of Public Health Ontario.

"One of the things that is very different is that we know what the virus is. We have a fast, reliable test and that really is a game changer."

More than 400 Canadians were diagnosed with SARS and 44 died as a result of the epidemic that killed almost 800 people worldwide in 2003.

Compared with the 2003 SARS outbreak, the flow of information worldwide and speed at which diagnostic tests have been developed has improved dramatically.

"The speed with which people identified SARS was amazing for 17 years ago, but it still took weeks," McGeer said. "Here, the problem was recognized the last week of December, tests were available around the world 10 days later."

A patient at Sunnybrook Hospital in Toronto is being treated in isolation for what Canadian health officials call the first 'presumptive' confirmed case of coronavirus. (Carlos Osorio/Reuters)

Information was hard to come by in the early days of the SARS epidemic, too, and health officials in Canada were caught off guard when the virus was confirmed to have landed in Toronto in March 2003.

McGeer said health-care workers were "unprepared to take precautions" during the SARS epidemic due to a lack of diagnostic tests and experience with outbreaks.

"If you had told people before SARS that a new disease would emerge in China and cause outbreaks in Toronto, they would have laughed you out of the room," she said.

"And the situation now is very different. We know what these risks are. We know how they're going to come at us and what you've seen is the perfect example of that working."

McGeer said the patient clearly received information that he needed to contact authorities when he had symptoms arise, which he did, and the sample was identified by officials within a day.

"Everybody took the right precautions," she said. "It's a world of difference."