Could the U.S. pulling out of the WHO could put Canadians at risk?

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Those working at the World Health Organization had been expecting the worst — but Donald Trump’s executive order still landed like a gut punch. 

“The mood here is pretty sombre and quite gloomy,” said Dr. Madhukar Pai, who happened to be working from WHO headquarters in Geneva when the U.S. president signed an executive order withdrawing America from the global health agency. 

The United States is slated to leave the WHO in January 2026, says the U.N, since it has to provide a year’s notice before withdrawing. The United States is by far the biggest financial supporter of the WHO, contributing 18 per cent of its overall funding, which amounts to roughly $1.2 billion for the agency’s most recent two-year budget for 2024-25.

It’s bad timing. Pai, who chairs the department of global and public health at McGill University, says there’s so much to do to curb the spread of infectious diseases around the world right now.

Bird flu – specifically H5N1 – could be just one mutation away from being more transmissible among humans, according to a peer-reviewed study published in Science in December. There’s currently an outbreak of the deadly Marburg virus in Tanzania, following a fatal outbreak in Rwanda in the fall of 2024. There are several outbreaks of mpox in multiple African countries, and there’s potential for the disease to spread outside the continent. 

Pai worries that weakening the WHO could be catastrophic, not just for Americans but for the entire world.

That, he says, should concern Canadians. 

“What happened in Wuhan came to Canada. What happened somewhere else will come to Canada.”

It’s a fear shared widely by other public health and infectious disease experts, who worry the move could also set back progress in fighting diseases like polio and malaria. Zimbabwe worries the move will hurt HIV/AIDS relief programs in the country and in other African nations, given that the withdrawal from the WHO could signal the U.S. might cut its foreign aid — something those programs rely upon. And Germany said Tuesday it would try to persuade the U.S. to reconsider pulling out of the WHO. 

‘50% chance’ of a COVID-scale pandemic by 2050

Every day, an estimated 400,000 people cross the Canada-U.S. border, the largest land border in the world. And there are about 800,000 Canadian citizens living in the United States. All this means the infectious disease threat could be even more pressing for Canadians.

Dr. Peter Singer, who was special adviser to the WHO director general between 2017 and 2023, says the decision will make Americans less healthy — and that’ll also affect Canadians. 

“If our biggest and best neighbour is not a member of WHO, that makes the world, the United States and Canada less safe from pandemics like the one we just went through,” said Singer, who is also a professor emeritus at the University of Toronto.

“Experts estimate there’s a 50-per-cent chance that a COVID-scale pandemic will happen between now and 2050. We have to be prepared for that.”

The WHO works with its member states to detect, monitor and manage public health threats. It’s a forum where countries share things like virus samples and gene sequences. By leaving the health agency, the U.S. may now have a blind spot, says Dr. Prabhat Jha, a professor of global health at the University of Toronto. 

“Other countries, in a future pandemic, may actually respond to the U.S. withdrawal by saying, ‘Well, we won’t share this information with the U.S.'”

“That then spills over into Canadian threats,” Jha said.

Pai puts it bluntly.

“If the U.S. is going to suffer in the future, we will suffer along with the U.S.” 

H5N1 and flu shots

Scientific co-operation is needed to fight pandemics and routine diseases alike — and that could be in jeopardy if the U.S. pulls out of the WHO, Jha says. 

One example: the annual flu shot.

“The flu shot is a product of a WHO network of 80 labs around the world that share essential information on the virus and help design this year’s flu shot. And that is actually really under threat,” Jha says. 

Information sharing also helps governments prepare for possible challenges, like the spread of bird flu. That free flow of information could also be at risk, says Devon Greyson, a professor at the University of British Columbia’s school of population and public health.

“If we don’t know what’s happening on the southern end of our bird-migration patterns, for example, it’s a little harder to prepare here.”

“Things like H5N1 don’t respect borders,” Greyson said. 

A ‘wake-up’ call for the world

But Jha does see a silver lining in all this. 

“It’s a wake-up call for the world, for other countries — including Canada —  to really think about what’s needed for collective action on health.” 

He says it’s a chance for the Canadian government to step up and fill in the leadership gap with the U.S. departure on the horizon.

Pai shares that hope. He says Canada’s already a global leader in reproductive health, mental health and human rights.

“I think this is actually a terrific opportunity for Canada to show leadership at a global level,” he said. 

Singer also says he does see an outcome where the WHO and the U.S. are able to come to an agreement.

“The best outcome is the situation is if the WHO and the U.S. could sit down together, engage, listen to each other’s concerns, and both come out strong,” he said. 

‘Good governance’

And if the U.S. does leave the WHO in the end, Singer says this could be a stark warning for Canada — it needs to take unilateral action to bolster the country’s pandemic preparedness. 

“This is a signal for the Canadian government, and governments around the world, to strengthen their own public health response and prepare for a weakened WHO,” Singer says. 

Greyson agrees.

“What we can do here is make sure that our systems are stable, that we have structures that will keep things funded, that will keep things running,” Greyson said.

“That is the sort of good governance … we pride ourselves on here in Canada.

“‘Peace, order and good governance,’ after all, is the Canadian answer to America’s ‘Life, liberty and the pursuit of happiness.'”