During the COVID-19 pandemic, politicians, scientists and media organizations vilified unvaccinated people, blaming them for prolonging the pandemic and advocating policies that barred “the unvaccinated” from public venues, businesses and their own workplaces.
But a peer-reviewed study published last week in Cureus shows that a key April 2022 study by Fisman et al. — used to justify draconian policies segregating the unvaccinated — was based on the application of flawed mathematical risk models that offer no scientific backing for such policies.
Dr. David Fisman, a University of Toronto epidemiologist was the lead author of the April 2022 study, published in the Canadian Medical Association Journal (CMAJ), which the authors said showed that unvaccinated people posed a disproportionate risk to vaccinated people.
Fisman has worked as an adviser to vaccine makers Pfizer, Seqirus, AstraZeneca and Sanofi-Pasteur. He also advised the Canadian government on its COVID-19 policies and recently was tapped to head up the University of Toronto’s new Institute for Pandemics.
Fisman told reporters the key message of the study was that the choice to get vaccinated is not merely personal because if you choose to be unvaccinated, you are “creating risk for those around you.”
The press ran with it.
Headlines like Salon’s, “Merely hanging out with unvaccinated puts the vaccinated at higher risk: study,” Forbes’ “Study Shows Unvaccinated People Are At Increased Risk Of Infecting The Vaccinated” or Medscape’s “My Choice? Unvaccinated Pose Outsize Risk to Vaccinated” proliferated in more than 100 outlets.
The Canadian Parliament used the paper to promote restrictions for unvaccinated people.
However, in the new study published last week, Joseph Hickey, Ph.D., and Denis Rancourt, Ph.D., show that Fisman’s “susceptible-infectious-recovered (SIR)” model, used to draw his conclusions, had a glaring flaw in one of its key parameters — contact frequency.
When they adjusted that parameter to account for real-world data, the model produced a variety of contradictory outcomes, including one showing that segregating unvaccinated people can increase the epidemic severity among the vaccinated — the exact opposite of what Fisman et al. purported to show
Hickey and Rancourt, researchers at Canada’s Correlation: Research in the Public Interest, concluded that without reliable empirical data to inform such SIR models, the models are “intrinsically limited” and should not be used as a basis for policy.
The Canadian researchers attempted to publish their paper in CMAJ, where Fisman had published his original study, but the editor — a collaborator of Fisman’s — refused even to review it.
The open-access version of CMAJ also declined to publish the article even after it received favorable peer reviews.
In a letter sent, with supporting documentation, to the CMAJ and the Canadian Medical Association, Hickey and Rancourt recounted the “tedious saga” whereby the journal editors “concocted a multitude of ancillary and unnecessary objections, apparently intended to be insurmountable barriers” to publishing their study.