The World Health Organization is clarifying statements made by its chief scientist about the safety and efficacy of mixing and matching COVID-19 vaccines, after comments at a briefing were taken out of context and caused confusion.
The Canadian experts stressed that the WHO officials’ statements are not related to the Canadian COVID-19 vaccination program and do not contradict the recommendations of the National Immunization Advisory Committee (NACI) and Public Health Agency Canada (PHAC).
At a briefing on Monday, WHO chief scientist Dr Soumya Swaminathan was answering a reporter’s question about whether or not a possible third dose – or booster – of COVID-19 vaccines is needed.
The question came on the heels of Pfizer’s announcement that it was seeking FDA approval for a third dose.
As part of a lengthy response, Swaminathan cautions individuals who decide for themselves whether or not they need additional doses.
“There is a tendency now for people in countries where there are enough vaccines to voluntarily start considering an additional dose, you know,” she said.
“It’s a pretty dangerous trend here where people are in … an area that is devoid of data and evidence as much as it gets mixed in,” she said. “It would be a chaotic situation in countries if the citizens started, you know, deciding when and who should take a second, third or fourth dose.”
But the headline that appeared in a short story published by Reuters that was picked up by other media outlets was “WHO warns against mixing and matching COVID vaccines”.
This has some readers worried about the Canadian vaccination approach, which involves mixing vaccines.
This title is misleading. Tweet embed from @Who is the He cautioned against “purchasing the vaccine” for individuals outside public health systems (and in some cases, getting fourth doses on their own). She did not say that individual countries’ vaccine policies were “dangerous”. 1/3 https://t.co/IgWn6dlwiu
A day later, Reuters issued a clarification on Twitter.
The news agency also updated the headline of the story to read as follows:The World Health Organization warns individuals against mixing and matching COVID vaccines.“
Clarification: The World Health Organization has made clear that public health agencies, not individuals, should make decisions about mixing and matching COVID vaccines, based on available data. We are deleting other tweets that lack context https://t.co/r3u0FKgvhb pic.twitter.com/ITjGM1PvPD
Was anyone talking about Canada?
No. Swaminathan was talking about the lack of evidence to support the need for an additional dose after someone has been fully vaccinated.
She also stressed the urgent need for vaccines to reach low- and middle-income countries where the majority of people did not even get their first dose to protect them from COVID-19, including the delta variant.
Is the World Health Organization suggesting that health agencies not recommend mixing doses?
No. In fact, the opposite is true.
“At our global press conference on COVID 19, Dr Somaya Swaminathan made it clear that individuals should not decide for themselves, and public health agencies can, based on the available data,” the World Health Organization said in a statement to CBC News on Tuesday.
Swaminathan also sent out a tweet to clarify her position when the misleading story was shared on Twitter.
Individuals should not decide for themselves, public health agencies can, based on the available data. Pending data from mixed and matching studies of different vaccines—immunogenicity and safety should be evaluated https://t.co/3pdYj4LUdz
“Context is very important,” infectious disease specialist Dr. Isaac Bogosh told CBC News on Tuesday.
WHO officials, he said, “were really referring to people who had already received, say, a full course of a series of vaccines, and then were, you know, for lack of a better word, choosing their own adventure and trying to get additional doses of a vaccine.”
Watch | Dr. Isaac Bogosh explains the advice on mixing vaccine doses:
Swaminathan said that guidance on mixing and matching vaccines should come from public health agencies – and that’s exactly what is happening in Canada.
“When public health agencies and advisory committees make recommendations, including mixed schedules, they are based on data,” said Dr. Caroline Quach Thanh, a pediatric infectious disease specialist and medical microbiologist at Chu Ste. Justin in Montreal. She is also the former president of NACI.
“We’re not just looking at immunogenicity and efficacy, but we also need to make sure the diet is safe,” Quach Thanh told CBC News on Tuesday.
Does the Canadian vaccination approach work?
Yeah. Infectious disease experts and epidemiologists broadly agree. As more people get vaccinated, cases of COVID-19 are rapidly declining across the country, as are hospitalizations and deaths.
“Completing your vaccine series with a second dose is essential for optimal, long-term protection against COVID-19 disease and associated serious outcomes,” PHAC said in an emailed statement to CBC News on Tuesday.
NACI’s recommendations on taking a different vaccine as a second dose were released on June 1, based on evidence and data from other countries – the kind of evidence-based approach advocated by the WHO’s chief scientist.
Canada has been mixing and matching COVID-19 vaccines for weeks based on research emerging from Spain and the United kingdom which found that the combination of AstraZeneca and Pfizer was safe and effective in preventing COVID-19.
Because both Moderna and Pfizer have mRNA vaccines, the NACI also said Can be used interchangeably.
“Vaccine interchangeability is not a new concept,” the PHAC Foundation said in its statement.
“Similar vaccines from different manufacturers are used when vaccine supplies or public health programs change. Different vaccine products have been used to complete the influenza, hepatitis A, and other series of vaccines.”