Canada’s requirement for travelers from China to test negative for COVID-19 will not help prevent new variants or the spread of the virus, experts say.
Kerry Bowman, an assistant professor at the University of Toronto’s Temerty Faculty of Medicine, called the requirement “absolutely a political move and not scientifically justified at this time.”
“These are not the early days of the pandemic,” he said. “So I think it’s largely political.”
The federal government said Saturday that people arriving from China, Hong Kong and Macau must test negative for COVID-19 before leaving for Canada.
The requirement applies to all air travelers aged two and over from the three countries and begins on January 5, it said.
China’s move away from strict COVID-19 control measures has led to widespread infection in that country, although not much is known about what different Omicron variants are in circulation, said Bowman, who teaches bioethics and global health.
“I don’t think it’s a great idea. I don’t think it makes us safer. On the surface, it looks like governments are being proactive, sensitive and protecting their citizens,” he said.
“But it’s pretty clear that point-of-entry screening isn’t very effective at all. Often people can test positive days and weeks later.”
dr Isaac Bogoch, an associate professor at the University of Toronto’s Temerty Faculty of Medicine, said it’s not entirely clear what the policy’s goals are, but such measures have not helped.
“We know from the past that very focused and targeted travel measures like this do not do much to prevent the spread of COVID, either by importing COVID into Canada or by threatening variants of concern in Canada,” he said.
Bogoch said it would have helped if China had been transparent with its COVID-19 data, variants, vaccine and spread.
“But let’s not pretend that if travelers from China require a negative PCR test before coming to Canada, it will affect Canada’s experience with COVID-19,” he said. “It won’t.”
Colin Furness, an assistant professor at the University of Toronto’s Faculty of Information, said the situation regarding travel requirements is complicated.
“This is both political and social and public health,” he said. “It’s probably perceived as political. It’s likely to be perceived as racist. Those are obviously not helpful things.”
But the government should be worried about new variants coming out of China, he said.
Caroline Colijn, a mathematics professor at Simon Fraser University in Burnaby, BC, said test requirements can likely reduce the import rate.
“If there is a new variant or just high levels of COVID in certain locations, the rate of direct importation from those locations will likely be reduced somewhat by requiring negative testing, but it will not prevent importation entirely,” said Colijn, it’s a Canada 150 Research Chair.
Isolating or quarantining travelers could help reduce the likelihood of chains of transmission forming after the trip, she said.
“So if we ask for negative tests, it just buys us a little bit of time.”
Governments and scientists must face the possibility that there might be “a more serious, more immune-invasive, more transmissible or more dangerous variant of this virus” and should make plans for next steps, she said.
While it’s not a popular view, Furness said it would be far more effective if all governments required negative COVID-19 tests and vaccinations on all flights.
“Let’s be clear,” he said. “COVID is everywhere. COVID is everywhere. These types of measures, which three years ago may have been enormously effective in limiting the spread, will not do much now.”
Research has shown how the virus spreads through human mobility, which means the next variant of the virus might not even come from China, and even if it did, it could end up in Canada through other indirect routes, Bogoch said.
Canada hasn’t been able to prevent variants like those seen in Alpha, which appeared in the UK, Delta, which was first discovered in India, and Omicron, which appeared in southern Africa, he said.
“From a scientific and medical point of view, just requiring a negative PCR test from Chinese travelers will not have much impact on Canada,” he said.
“And unfortunately that’s how it is. We can take action to reduce the burden of COVID in Canada, but we will not stop the introduction of this infection.”
A more effective measure, Bowman said, would be to test aircraft and airport sewage to check for viral loads and mutations.
Vancouver International Airport said Saturday it would expand its wastewater testing pilot program.
One of the variants, XBB.1.5, which is a cause for concern and is spreading quickly, is already in North America, Bowman said.
“It’s so important that we remain evidence-based,” he said.
“I think in the years to come as this story gets told, when we have a level of objectivity that I don’t think any of us really have, including me – if we’re really remote from that – I think when we look at that Globally, we’re going to see that we’ve done a lot of things that were much more political than evidence-based.”
China, unlike most of the West, hasn’t used mRNA shots, meaning variants from that country may be more contagious but also more susceptible to the vaccines in that part of the world, Furness said.
“That’s plausible. But here, too, it’s all speculation.”
Bogoch said the virus that causes COVID-19 continues to mutate.
Most people in Canada have some form of immunity through a combination of vaccines and previous infections, he added.
Around the world, he said it would help people if there was more sequencing of data that would help identify and understand emerging variants.
“Unfortunately, less and less is being sequenced.”
But people, especially the elderly and those with other health conditions, should be empowered to protect themselves, he said. Masking indoors can also reduce the likelihood of infection.
“As we look into the foreseeable future, we will see ebbs and flows of COVID-19 in the community. We’re going to have periods when it’s higher, we’re going to have periods when it’s lower, just like ours. that I’ve seen in the last two years,” Bogoch said.
“And hopefully future waves of COVID will have less and less of an impact as we move forward.”
This report from The Canadian Press was first published on January 1, 2023.