Public-health officials and medical experts are warning that immunity passports or encouraging people to become infected with COVID-19 to hasten a reopening of society and the economy are risky strategies that could backfire.
They’ve issued their cautions as provinces and countries around the world explore possible ways to reopen businesses and public services during the global pandemic.
New Brunswick started its phased reopening last week after seeing no new COVID-19 cases for several days, while Saskatchewan, which has maintained a low case count, is moving forward with its reopening strategy early next month. Last week, Quebec Premier François Legault said the province is considering opening society to allow people who aren’t in high-risk groups to become infected, which could help the province achieve herd immunity. Ontario is set to release its reopening plan this week.
Some countries, including Chile, are planning to test people for antibodies to COVID-19 to determine who has been infected and recovered. Those that have would receive immunity certificates or passports, which would allow them to return to school or work.
But too much is unknown about COVID-19 – particularly how long people remain immune after becoming infected – to look at passports or other measures as a workable solution, said Isaac Bogoch, an infectious diseases physician at Toronto General Hospital.
“As of today, it’s just not safe to think that,” Dr. Bogoch said.
Theresa Tam, Canada’s Chief Public Health Officer, said on Saturday the idea of immunity passports is “premature” given how little is known about how people develop immunity to the coronavirus that causes COVID-19 and how long the protection lasts. Dr. Tam also said that allowing people to become infected in order to achieve herd immunity is far too risky, as it’s not yet understood who will develop a severe illness as a result of the virus.
Infectious disease experts around the world have cautioned against such an approach, saying that herd immunity could lead to an explosion in COVID-19 cases and quickly overwhelm hospitals.
The World Health Organization generated controversy when it waded into the immunity discussion over the weekend, with a tweet thread that incorrectly stated there is “no evidence” people infected with COVID-19 develop antibodies and are protected from a second infection.
The WHO later deleted the tweets and clarified that while people do develop antibodies in response to COVID-19, there are unanswered questions about “the level of protection or how long it will last.”
For that reason, the WHO, along with Canada’s top health officials and many other infectious disease experts, warn against relying on immunity passports.
Dr. Bogoch said one of the main challenges is that many of the tests used to detect antibodies to COVID-19 are unreliable and don’t produce accurate results.
“With the data that we have today, it’s just not responsible to think that if you have an antibody test, that means you’re immune and you can safely reintegrate at a place of work or in a place where people congregate together,” he said.
But in the coming months, that could change, Dr. Bogoch said, as researchers around the world work to find answers to some of the most challenging aspects of COVID-19.
In the meantime, Dr. Bogoch said that provinces that are able to keep their case counts of COVID-19 low will likely be able to reopen, as long as they approach it carefully and slowly. But some parts of the country, like Ontario, continue to see a high number of cases and likely will have to wait longer before parks, schools, restaurants and other businesses reopen, Dr. Bogoch said.
“It’s not just enough to flatten [the curve]. We’ve got to get down to the other side of the curve before we open it and that could be weeks away.”
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