Experts monitoring the spread of China’s new coronavirus say that Canada’s risk level for an outbreak is still unclear, but it’s a level that can evolve and increase as global infections continue to skyrocket.
According to Dr. Kamran Khan, one of the reasons why assessing Canada’s risk level remains difficult to assess is because there’s no non-stop flights from Wuhan, the Chinese city in which the virus was first detected, to Canada.
It means that it would be hard to track travellers who have been to the city, as they would have to take a connecting flight at a larger, international airport — usually via Beijing.
Khan, who is an infectious disease physician and founder and CEO of global disease tracker BlueDot, was able to alert global health authorities to its spread once he first detected the virus in late December.
But with the U.S. confirming its first infection in Washington state Tuesday, Khan said the disease is now turning into an outbreak with global reach.
According to Wilfrid Laurier University professor and virologist Stephanie DeWitte-Orr, another factor that has made it difficult for Canada and other countries to detect the virus is its long incubation period, which can range anywhere between one and two weeks.
“You can be infected and not know you’re infected,” said DeWitte-Orr.
“So you could go to Wuhan, get infected and come back, which is what happened to the individual in Washington and then be home for a number of days, interacting with people before you even know that you’re sick.”
The virus, dubbed the 2019-nCoV, is part of the coronavirus family — the same species of virus as the SARS and MERS viruses.
While the definitive origin of the virus has not been confirmed, most of its first cases were linked to a seafood market in Wuhan.
“It likely originated in some non-human animal and jumped to a human,” said Dr. Isaac Bogoch, an infectious disease specialist at Toronto General Hospital.
“In markets, or anywhere where non-human animals and humans have close contact with each other, we see this happen.
“Certainly, that’s what happened with the SARS outbreak in 2002.”
Dr. Theresa Tam, Canada’s chief public health officer, previously said that the risk for Canadians contracting the virus remains low.
Ontario’s chief medical officer of health, Dr. David Williams, also said that Canada is in a much better position to respond to the outbreak in comparison to 17 years ago, when the SARS outbreak had killed more than 900 people worldwide — 44 Canadians included.
To date, China’s new virus has already killed 17 and infected a confirmed 555 others around the world with pneumonia-like symptoms.
Infections have so far been confirmed in Japan, Taiwan, South Korea and Thailand, along with the U.S. and China.
Canada, which currently has no confirmed cases of the virus, will start screening at certain airports in a bid to identify travellers that have visited Wuhan.
All international travellers arriving to Toronto, Montreal and Vancouver international airports will be asked screening questions in the next several days, according to a statement from the Canadian Border Services Agency.
According to the CBSA, there remains a “high likelihood that travellers on connecting flights from Wuhan will be arriving in Canada.”
According to Khan, screening wouldn’t be the most effective form of disease intervention, but would still present another opportunity at hand.
“We screen millions of people and did not detect a single person with SARS,” said Khan, pointing to the 2003 outbreak of the disease that hit Toronto and cities around the world.
“But, I think it’s an opportunity to engage travellers and educate them and let them know what they need to do, should they develop illness, so that we can reduce the time to diagnosis and reduce the potential that others around them might get infected.”
— With files from Rachael D’Amore, Leslie Young and Maham Abedi
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