Immunity passports and herd infection: “just not sure” ways to reopen society, warn health officials


Ontario – the provincial legislature seen here on April 25, 2020 – is expected to release its reopening plan this week.


Public health officials and medical experts warn that immunity passports or encouraging people to become infected with COVID-19 to accelerate the reopening of society and the economy are risky strategies that could backfire.

They have issued their warnings as provinces and countries around the world explore possible ways to reopen businesses and public services during the global pandemic.

New Brunswick started its gradual reopening last week after having seen no new cases of COVID-19 for several days, while Saskatchewan, which has maintained a low number of cases, is moving forward with its strategy reopening early next month. Quebec Premier François Legault said last week that the province is considering opening society to allow people who are not part of high-risk groups to become infected, which could help the province to obtain collective immunity. Ontario is expected to release its reopening plan this week.

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Some countries, including Chile, plan to test people for anti-COVID-19 antibodies to determine who has been infected and recovered. Those who received it would receive immunity certificates or passports, which would allow them to return to school or work.

But too little is known about COVID-19 – especially the length of time people remain immune after being infected – to consider passports or other measures as a viable solution, said medical specialist Isaac Bogoch infectious diseases at Toronto General Hospital.

“To date, it’s just not safe to think that,” said Dr. Bogoch.

Theresa Tam, Chief Public Health Officer of Canada, said on Saturday that the idea of ​​immunity passports was “premature” given the little knowledge of how people develop immunity to the coronavirus that causes COVID-19 and the duration of protection. Dr Tam also said that it is far too risky to allow people to be infected in order to benefit from collective immunity, as it is not yet clear who will develop serious illness as a result of the virus.

Infectious disease experts around the world have warned of such an approach, saying that collective immunity could explode COVID-19 cases and quickly overwhelm hospitals.

The World Health Organization sparked controversy when it launched into the immunity discussion this weekend, with a tweet thread that incorrectly stated that there was “no evidence” that people infected with COVID-19 develop antibodies and are protected against a second infection.

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The WHO later deleted the tweets and clarified that, although people develop antibodies in response to COVID-19, there are unanswered questions about “the level of protection or the duration of protection”.

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For this reason, WHO, along with Canada’s senior health officials and many other infectious disease experts, warn against the use of immune passports.

Dr. Bogoch said one of the main challenges is that many tests used to detect anti-COVID-19 antibodies are unreliable and do not produce accurate results.

“With the data we have today, it is just not responsible for thinking that if you have an antibody test, it means that you are immune and that you can safely reintegrate into the workplace or in a place where people gather, “he told me.

But in the coming months, that could change, said Dr. Bogoch, as researchers around the world try to find answers to some of the more difficult aspects of COVID-19.

In the meantime, Dr. Bogoch said provinces that are able to maintain a low number of COVID-19 cases will likely be able to reopen, as long as they approach it slowly and carefully. But parts of the country, like Ontario, continue to see a high number of cases and will likely have to wait longer before parks, schools, restaurants and other businesses reopen, said Dr. Bogoch.

“It is not enough to flatten [the curve]. We have to go down the other side of the curve before we open it and it could be weeks. ”

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