Canadian COVID-19 vaccine study seized by anti-vaxxers – highlighting dangers of early pandemic research
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A Canadian study that grossly underestimated the protection offered by COVID-19 vaccines against the Omicron variant is being reviewed – but not before it was widely shared on social media by anti-vaxxers, academics and even the creators of the Russian vaccine Sputnik V.
Ontario pre-publication study, which has not yet been peer-reviewed, suggested that three doses of COVID-19 mRNA vaccines were only 37% effective against Omicron infection, while two doses actually showed protection. negative.
The preprint was shared on Twitter more than 15,000 times in the two weeks following its publication, according to Altmetric, a company that tracks where published research goes online. It’s in the top 5% of all searches ever tracked.
The group behind Sputnik V shared the results to his one million Twitter followers earlier this month, saying the study showed the “negative efficacy” of two doses of mRNA vaccine and the “rapidly waning efficacy” of a booster. The group did not respond to questions from CBC News.
Dr. Vinay Prasad, associate professor of epidemiology at the University of California-San Francisco, also shared on Twitter, asking why the US Food and Drug Administration (FDA) and Centers for Disease Control (CDC) would advise a recall for Omicron.
Study updating the results with entirely different results
But the paradoxical results were later found to have been influenced by behavioral and methodological issues, such as the timing of the observational study, how vaccine passports altered individual risk, and changes in access to COVID-19 testing. 19.
The results are currently being updated with additional data that showed completely different results, said Dr. Jeff Kwong, the study’s lead author and epidemiologist and senior scientist at the Institute for Clinical Evaluative Sciences (ICES) in Toronto. .
“We are in the process of adding two more weeks of data and it appears that there are no more negative VEs (vaccine efficacy). Our results are now more in line with data from the UK where it is lower, sure, compared to Delta, but never going negative,” he told CBC News.
“And then a higher VE with the boost. So I think that’s good news and we’re just running those scans and hopefully having an updated version, version two, by the time next week.”
A recent report of the Imperial College London COVID-19 response team found that while Omicron largely eludes immunity from prior infection and two doses only provide zero to 20% protection, three doses increase it between 55 and 80%.
This means that the updated preprint could end up showing that Omicron protects against infection more than twice as originally reported. On Friday, the preprint study remained unchanged on the medRxiv website where it was posted.
CBC cited the study in an analysis story last week, but has since removed the reference to it until the data is updated.
The study was also highlighted by the federal government COVID-19 Immunity Task Force earlier this week, before the discrepancies in the data were discovered.
“We contacted Dr. Kwong and indeed he informed us of new data on Monday evening,” a spokesperson said in response to CBC News, raising concerns about the accuracy of the study.
“As this week’s data changes things, we have withdrawn the preprint of our magazine which is being sent out today.”
Dr. Danuta Skowronski, vaccine effectiveness expert and chief epidemiologist at the BC Center for Disease Control, who developed the vaccine study design used in the preprint, published a remark calling for “extreme caution” with last week’s results.
“If you have a negative estimate, you want to start looking, OK, well, which subgroup is causing this and why?” she told CBC News.
“Are these the asymptomatic? Are these the symptomatic? Are these people who have been screened for labor? Are these people who have had a rapid antigen test What group is behind this paradoxical discovery?
Skowronski said that until these questions are resolved, “all bets are off” on the interpretation of the results and “the validity of the study must be questioned.”
“In the real world, we can’t control people’s behavior, and so these studies are likely to lack comparability between vaccinated and unvaccinated,” she said, adding that vaccine passports significantly change the risk of exposure in Ontario.
“There’s good reason to believe that the very small fraction of people who are still unvaccinated – that group is now quite different from vaccinated people.”
The study has spread like wildfire with anti-vaccines online
The study highlights how quickly early results from studies that have not been peer-reviewed can spread online in the pandemic and how inaccurate results can be weaponized to fit into a program before they can be corrected.
Many of those who shared the study on Twitter used anti-vaccination rhetoric to argue that boosters didn’t work against COVID-19, while others posited that vaccines shouldn’t have been approved for emergency use by the FDA in the first place because they did not meet its initial 50% efficiency threshold.
“It will certainly be used by bad actors to shore up support for their opinions on the lack of efficacy of vaccination against COVID-19,” said Ahmed Al-Rawi, assistant professor at the School of Communication at the Institute. Simon Fraser University, specializing in disinformation.
“I would immediately take it down and make public statements about the inaccurate study results, as it has been widely shared on social media and it will only confuse people further.”
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The study also did not notably examine the protective vaccines offered against severe COVID-19, which turned out to be much higher than against infection with Omicron alone – something Kwong says he and his colleagues will add in a future release.
Although COVID-19 vaccines do not offer complete protection against infection, they work well to prevent serious illness. New data from the Public Health Agency of Canada found that Canadians who received two doses were 19 times less likely to be hospitalized than those who had not been vaccinated.
“Several studies have shown modest protection from two doses against Omicron infection, but better protection against serious consequences such as hospitalization,” said Marc Lipsitch, epidemiologist at Harvard TH Chan School of Public Health. in Boston.
“This benefit goes beyond any possible benefit of preventing infection or transmission.”
Lipsitch said Skowronski’s criticisms of the study are valid. He cautioned against comparing positive cases among those with symptoms with those who have not been tested for different reasons, adding that he fully agrees that this approach can be a source of “substantial bias”. .
“When investigators try to share early results in the interest of public health, as these people have done, there is often a lot of uncertainty in those estimates,” said Dr. David Fisman, epidemiologist at the Dalla Lana School of Public Health at the University of Toronto. .
“But it’s very hard to recover from that once people start using early versions of your work to support misinformation.”
Skowronski said the rapid sharing of COVID-19 vaccine studies on social media has completely changed the research landscape, adding more pressure to get early results.
“You must be wondering why do we have to release it now? Why can’t it wait a week or two? What impact will that have on public and political decision-making?” says Skowronski.
“And if you can’t answer that, then we really should be asking ourselves, why are we rushing into preprint?”
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Skowronski published a to study in 2010 showing paradoxical negative vaccine efficacy during the 2009 H1N1 influenza pandemic which found that those who had been vaccinated against influenza were more likely to be infected with the influenza strain than people who had not , which was later has proven itself.
But she first assumed the results were methodologically inaccurate, contacted outside experts around the world, conducted several different studies, and worked with an international panel of experts.
“I learned the lesson the hard way in 2009 dealing with paradoxical findings and the level of rigor required,” she said. “You don’t approach this casually – it takes a lot of thinking, a lot of worrying – before you can get to that.”
Dr. Ivan Oransky, co-founder of Retraction watch, a website that tracks errors in scientific journals, said that because the study was found to be “flawed,” the researchers should act quickly to update their findings.
“They’re doing the right thing. The question is how fast are they going to do it?” he said. “I mean, they’re talking about next week…but it’s kind of an eternity these days.”