Prime Minister Justin Trudeau says it’s premature to talk of so-called “immunity passports” for Canadians because the science is unclear about whether people who have recovered from COVID-19 are protected from catching it a second time.
As provinces begin opening up their economies from COVID-19 lockdowns, Trudeau said on Saturday none of those recovery plans hinge on people being immune to catching COVID-19 twice.
Trudeau said he spoke to premiers Friday and they discussed a basic framework that provinces will use as they re-open businesses, schools and other institutions. The focus, he said, is on preventing the spread of the virus through physical distancing and personal protective equipment.
“It is very clear that the science is not decided on whether or not having had COVID once prevents you from having it again,” he told reporters. “It’s something we need to get clearer answers to and until we get those clearer answers, we need to err on the side of more caution.”
Trudeau was responding to a recent World Health Organization brief stating there is no evidence that people who have recovered from the virus have antibodies that protect them from getting infected again.
The WHO issued the brief in the context of certain countries announcing the possibility of providing so-called “immunity passports” or “risk-free certificates” to citizens who have already been infected.
The practice could actually increase the risks of spreading coronavirus, as people who have recovered may ignore advice on taking precautions.
Chile said last week it would begin handing out “health passports” to people who had developed antibodies to the virus. They could immediately rejoin the workforce.
The WHO said it continued to review the evidence on antibody responses to COVID-19.
Most studies have shown those who have recovered do have antibodies to the virus. But others have shown very low levels of neutralizing antibodies in their blood, which suggests an immune response that does not involve antibodies may be critical for recovery.
Provinces have varying approaches to relaxing public health orders that were put in place to limit the spread of the novel coronavirus.
Newfoundland and Labrador and Nova Scotia, for instance, continue to urge citizens to stay home as much as possible, while New Brunswick announced Friday low-risk outdoor activities such as golf, hunting and fishing were permitted to resume.
Ontario and Quebec announced they would present their recovery plans next week. Quebec Premier Francois Legault said his government would detail separate plans for schools and then for businesses.
Legault and the province’s director of public health, Dr. Horacio Arruda, have been pushing the idea of “herd immunity” as an approach to re-opening schools. That strategy involves exposing a large proportion of Quebecers to the novel coronavirus in a measured, gradual way, to help them develop a natural immunity.
That theory follows the logic of a vaccination program. When people receive a vaccine, they are given a weakened form of the virus, allowing their immune system to build antibodies to kill it.
“The idea is to go very gradually so that people who are less at risk can develop antibodies to be able to become immune,” Legault told reporters earlier in the week.
But Dr. Theresa Tam, Canada’s Chief Public Health Officer, warned against that approach Saturday. She said the federal government has put in place an immunity task force that will investigate how people’s immune systems are responding to COVID-19.
She said that since many Canadians have followed physical distancing orders, the percentage of the immunized population is “quite low.” And despite evidence that the virus is particularly dangerous to older people and those with underlying health conditions, younger people are still at risk.
“So the idea of generating natural immunity is actually not something that I think should be undertaken,” she said. “I personally think that as medical officers, we would be extremely cautious about that kind of approach.”
Canada’s death toll from COVID-19 rose 7 per cent to 2,350 from a day earlier. Cases reached more than 44,000.
Also Saturday, Trudeau announced funding for the country’s fish and seafood processors whose businesses were harmed by the coronavirus pandemic.
The government will spend $62.5-million to support the processors, he said. They can use the money to buy protective equipment for workers or storage space for products to sell them later.
The prime minister said the funding can also help pay for other equipment such as freezers, so that companies can store food products while they adapt their factories to ensure workers can maintain a safe distance from one another.
Fish and seafood are among the country’s top food exports and the industry employs roughly 72,000 people.
With a report from Reuters
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