'Most of the city is evacuating': Gridlock on Alberta highway after evacuation order in Fort McMurray
Four Fort McMurray neighbourhoods were ordered to evacuate on Tuesday as a wildfire gets closer to the city.
A new study that looks back on the first and second waves of the pandemic in 2020 and 2021 says that travel restrictions barring entry to Canada did drastically reduce the number of COVID-19 cases entering the country.
However, researchers say, it still wasn’t enough to stop new outbreaks.
In the study, published in the peer-reviewed journal eLife on Tuesday, researchers with the University of British Columbia looked at public data on viral genome sequences collected in 2020 and early 2021 to find the geographic source of specific chains of COVID-19 transmission.
They found that four weeks after Canada restricted entry from most foreign nationals in March 2020, the number of COVID-19 cases crossing the border into the country had dropped 10-fold.
“COVID-19 importations were accelerating in the lead up to March 2020 but experienced a sharp and drastic decline after travel restrictions were put in place,” Angela McLaughlin, a PhD candidate in bioinformatics at UBC and the study’s lead author, said in a press release.
“The data shows that federal travel restrictions can be effective in reducing viral importations when implemented rapidly.”
But COVID-19 was already here, and travel restrictions couldn’t stop that.
The spring and summer of 2020 saw daily case levels at one of their lowest nationally, but circulation was still occurring within the country, the study outlined, with specific chains of transmission persisting into the fall of 2020.
As travel restrictions eased in November 2020, allowing more entrance into the country as well as shortened quarantine requirements, the international importation of COVID-19 cases rebounded.
Variants of concern, beginning with the Alpha variant, began to make their way into Canada. Researchers estimated 30 unique genetic sublineages of the Alpha variant, also known as B.1.1.7, had entered the country by the end of February 2021.
Numerous factors, such as the state of the global fight against COVID-19, including the emergence of these variants elsewhere in the world, make it harder for travel restrictions to have an impact later on in the pandemic, researchers said.
“Travel restrictions have a diminishing return if domestic transmission is high, if highly transmissible variants become widespread globally, or if there are many individuals exempt from travel restrictions and quarantine without access to rapid testing,” says McLaughlin.
On March 21, 2020, in response to the pandemic, the U.S. and Canada mutually closed the border to recreational travel after having already shut its borders to most non-citizens looking to enter the country.
Within a month after these restrictions, researchers found that importations of COVID-19 declined from 58.5 sublineages of the virus on average per week to just 10.3-fold lower within four weeks.
There were still “newly seeded sublineages” over the summer of 2020 as domestic transmission continued. Travel restrictions were relaxed slightly in the fall, although the U.S. land border did not re-open to non-essential travel until August 2021.
During the first wave of the pandemic in early 2020, 49 per cent of viral importations of COVID-19 into Canada likely came from the U.S., the study found, entering primarily through Quebec and Ontario.
The U.S. was still the biggest international source of COVID-19 for Canada in the second wave, according to the data, at 43 per cent. Cases from India made up 16 per cent of those that came from outside of the country in the second wave, while cases from the U.K. made up seven per cent.
If restrictions had been kept at their maximum for longer, they could’ve held off more transmission, researchers posited, but this would’ve come with consequences in other areas.
“The social and economic repercussions of travel restrictions must be weighed relative to the risk of unhampered viral importations, which have the potential to overburden the health-care system,” Mclaughlin said.
“We are now in the era of infectious disease,” Dr. Jeffrey B. Joy, an assistant professor at UBC’s department of medicine and the study’s senior author, said in the release. “This study highlights the increasing importance of genomic epidemiology, enabled by sharing of genomic sequence data, in informing and evaluating public health policy to combat current and future viral outbreaks threatening society.”
____
CTVNews.ca wants to hear from Canadians with any questions.
Tell us what you’d like to know when it comes to rules around entering or leaving Canada.
To submit your question, email us at dotcom@bellmedia.ca with your name, location and question. Your comments may be used in a CTVNews.ca story.
Four Fort McMurray neighbourhoods were ordered to evacuate on Tuesday as a wildfire gets closer to the city.
Saskatchewan RCMP have revealed that a historic sexual assault investigation has led to the discovery of alleged crimes against children dating back to 2005.
Less than a week after two public sculptures featuring a livestream between Dublin, Ireland, and New York City debuted, 'inappropriate behaviour' in real-time interactions between people in the two cities has prompted a temporary shutdown.
The Edmonton Oilers will start Calvin Pickard in net Tuesday for Game 4 of their playoff series with the Vancouver Canucks.
The Biden administration has told key lawmakers it is sending a new package of more than US$1 billion in arms and ammunition to Israel, two congressional aides said Tuesday.
King Charles III has unveiled the first portrait of the monarch completed since he assumed the throne, a vivid image that depicts him in the bright red uniform of the Welsh Guards against a background of similar hues.
The annual list of Canada's top restaurants in the country was just released and here are the places that made the 2024 cut.
Canadian LifeLabs customers who filed an application for a class-action settlement began receiving their payments this week, though at a much lower amount than initially expected.
Nearly 1,000 wildfires have burned across Canada so far this year. Here's an overview of the situation in Canada.
A team is ready to help an entangled North Atlantic right whale in the Gulf of St. Lawrence.
A $200 reward is being offered by a North Vancouver family for the safe return of their beloved chicken, Snowflake.
Two daughters and a mother were reunited online 40 years later thanks to a DNA kit and a Zoom connection despite living on three separate continents and speaking different languages.
Mother's Day can be a difficult occasion for those who have lost or are estranged from their mom.
YES Theatre Young Company opened its acclaimed kids’ show, One Small Step, at Sudbury Theatre Centre on Saturday.
An Ottawa pizzeria is being recognized as one of the top 20 deep-dish pizzas in the world.
A family of fifth generation farmers from Ituna, Sask. are trying to find answers after discovering several strange objects lying on their land.
A Listowel, Ont. man, drafted by the Hamilton Tigercats last week, is also getting looks from the NFL, despite only playing 27 games of football in his life.
The threat of zebra mussels has prompted the federal government to temporarily ban watercraft from a Manitoba lake popular with tourists.