Canada has opened up its borders to fully vaccinated foreign travellers. Are there risks?

While the Canadian government has implementedstrongmeasures to ensure fully vaccinatedforeign travellers coming into Canada won't be a significant source of COVID-19 spread,thoseprotectionswill certainly not eliminate the risk, medical expertssay.

"Certainly the optics aren't ideal, as we are in a fourth wave and cases continue to climb across the country," said Dr. Isaac Bogoch, an infectious diseasespecialistand member of Ontario's COVID-19 vaccine task force.

Under the measures, travellers must be fully vaccinated with a Canadian-approved vaccine at least 14 days prior to arriving and have receiveda negative COVID-19 test within 72 hours of their scheduled flight or their arrival at a land border crossing requirementsthat, while not perfect, are "very very good" atensuringpeople coming don't have COVID-19, Bogoch said.

"It's not foolproof, it's not ahermetically sealed border, we'll still have cases of COVIDintroduced. It's just going tobe fewer than if we had no protection whatsoever," he said.

On Tuesday,Canada openedits borders tofully vaccinated non-essential foreign travellers from across the globe, allowingthem to skip the14-day quarantinerequirement. Canada is currently in the midst ofa fourth wave of COVID-19 fuelled by the delta variant. However, most of the country's cases and hospitalizations areamong the unvaccinated.

Low test positivity rate at border

According to the Canada Border Services Agency (CBSA),the volume of travellers has increased in recent months, but the border test positivity ratefor COVID-19 has remained low. For example, between Aug.9 and 26, the positivity rate for fully vaccinated travellers randomly selected for testing at bordercrossings was 0.19 per cent(112 positive tests out of 58,878 completed), the CBSA said.

Still,Dr. Donald Vinh,an infectious diseases expert at the Research Institute of the McGill University Health Centre in Montreal, expressed concern that the federal government formulated theopen border policy forforeign travellers back in early July, when the delta variant wasn't as much of an issue in Canada.

Vinh said that plan was based on the assumption that those fully vaccinated were not only protected from infection but would not be a major source of transmission. Instead, the delta variant has shown that fully vaccinated people can still be infectedand still transmit the virus, he said.

Meanwhile, the full rate of breakthrough cases those in which a person has been infected despite being fully vaccinated is still unknown, he said.

"If we had no or low rates of community transmission right now, you could argue that our perhaps more relaxed approach could be acceptable," Vinhsaid. "We already have high, high, high rates of transmission across the country. So now what we don't want to do is be literally adding fuel to the fire."

The government has introduced special requirements for travellers arriving from India or Morocco. Due to a recent surge in COVID-19 cases, all direct passenger flights from India have been suspended until Sept. 21 and from Morocco until Sept. 29. Currently, air passengers from those countries can only enter Canada if they show proof of a negative test taken in a different country and depart from that country to come to Canada.

'Viruses do cross borders'

Dr. Marek Smieja,scientific director of McMaster HealthLabs and a professor of pathology and molecular medicineat McMaster University in Hamilton, suggested there should be some concernabout the potential of imported variants. He noted that thealpha and delta variants were both imported into Canadafrom abroad.

"Viruses do cross borders. And the question is: What's the most prudent way of allowing a reasonable amount of travel?" he said. "There's no doubt there will benew variants."

But the best protectionis to eliminate the domestic cases,so if thelocal COVID-19 levels are very low, health officials will recognize new variantscoming in, he said.

"The way you pay attention to imported diseases to get rid of local disease," Smiejasaid. "I would love to get to the point with COVIDwhere the only cases you see are imported outbreaks."

The federal government's measures, in terms of what's practical, area "pretty reasonable reassurance" that foreign travellers will be a very low risk, he said.

In terms of potential exposure to COVID, a foreign traveller who's fully vaccinated and tested coming into Canada is likely safer than those many people encounter on a daily basis,Smieja said.

Neighbour poses higher risk

"I would argue thatthe neighbour in the supermarket who isn't wearing their mask properly above their nose and actually hasn't been vaccinated is a higher risk than the person crossing a border," Smieja said. "I actually think it is a prudent thing to be making it easier for people to travel, particularly for those who are fully vaccinated."

Dr. Zain Chagla, an infectious diseases physician at St. Joseph's Healthcare Hamilton and an associate professor at McMaster University, agreed that it's more important tofocus on the pandemic's domestic situation.

WATCH | Travel protections to Canada are strong but not perfect, says specialist:

International travel protections to Canada are strong but not perfect, says specialist

3 years ago

Duration 1:32

There are strong layers of protection to stop the transmission of COVID-19 from international travellers entering Canada, but the country should also focus on getting more vulnerable Canadians vaccinated, says Dr. Isaac Bogoch, an infectious diseases specialist in Toronto. (Darryl Dyck/The Canadian Press)

With foreign travellers, he said, there's always going to be a risk, and some breakthrough cases, butthe government has come up with agood compromise.

"Thebottom line is we are going to have to do this at some point in time, and there will be another variant. The world is not completely immunized by any means," Chagla said.

"We're taking a calculated risk, we're following data ... to see that, yes, no cases are being generated in Canada or not very many are being generated in Canada as a result of this [foreign traveller policy]."