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.”
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EDMONTON – RCMP say a second suspect has been arrested in the killing of an Alberta county worker.
Mounties say 28-year-old Elijah Strawberry was taken into custody Friday at a house on O’Chiese First Nation.
Colin Hough, a worker with Rocky View County, was shot and killed while on the job on a rural road east of Calgary on Aug. 6.
Another man who worked for Fortis Alberta was shot and wounded, and RCMP said the suspects fled in a Rocky View County work truck.
Police later arrested Arthur Wayne Penner, 35, and charged him with first-degree murder and attempted murder, and a warrant was issued for Strawberry’s arrest.
RCMP also said there was a $10,000 reward for information leading to the arrest of Strawberry, describing him as armed and dangerous.
Chief Supt. Roberta McKale, told a news conference in Edmonton that officers had received tips and information over the last few weeks.
“I don’t know of many members that when were stopped, fuelling up our vehicles, we weren’t keeping an eye out, looking for him,” she said.
But officers had been investigating other cases when they found Strawberry.
“Our investigators were in O’Chiese First Nation at a residence on another matter and the major crimes unit was there working another file and ended up locating him hiding in the residence,” McKale said.
While an investigation is still underway, RCMP say they’re confident both suspects in the case are in police custody.
This report by The Canadian Press was first published Sept. 13, 2024.
RICHMOND, B.C. – The Integrated Homicide Investigation Team says the 26-year-old son of a man found dead on British Columbia’s Sunshine Coast has been charged with his murder.
Police say 58-year-old Henry Doyle was found badly injured on a forest service road in Egmont last September and died of his injuries.
The homicide team took over when the BC Coroners Service said the man’s death was suspicious.
It says in a statement that the BC Prosecution Service has approved one count of first-degree murder against the man’s son, Jackson Doyle.
Police say the accused will remain in custody until at least his next court appearance.
The homicide team says investigators remained committed to solving the case with the help of the community of Egmont, the RCMP on the Sunshine Coast and in Richmond, and the Vancouver Police Department.
This report by The Canadian Press was first published Sept. 13, 2024.
VANCOUVER – Mediated talks between the union representing HandyDART workers in Metro Vancouver and its employer, Transdev, have broken off without an agreement following 15 hours of talks.
Joe McCann, president of Amalgamated Transit Union Local 1724, says they stayed at the bargaining table with help from a mediator until 2 a.m. Friday and made “some progress.”
However, he says the union negotiators didn’t get an offer that they could recommend to the membership.
McCann says that in some ways they are close to an agreement, but in other areas they are “miles apart.”
About 600 employees of the door-to-door transit service for people who can’t navigate the conventional transit system have been on strike since last week, pausing service for all but essential medical trips.
McCann asks HandyDART users to be “patient,” since they are trying to get not only a fair contract for workers but also a better service for customers.
He says it’s unclear when the talks will resume, but he hopes next week at the latest.
The employer, Transdev, didn’t reply to an interview request before publication.
This report by The Canadian Press was first published Sept. 13, 2024.
