As vaccine coverage blankets the country, ushering in hope for a return to normal, Pfizer announced Thursday that it’s prepping a COVID-19 booster shot to make sure things keep trending in the right direction.
There’s just one problem, according to experts. We might not actually need it.
Preventing severe outcomes is the key to quashing COVID-19’s impact on our daily lives, according to the experts. Lockdowns and restrictions come into play when hospitalizations start to push the health care system’s capacity to its outer limits.
But with vaccines proving highly effective at preventing severe outcomes, experts say any conversations about boosters are still premature.
“I don’t think there’s good clinical evidence,” said Dr. Zain Chagla, an infectious disease specialist, on whether there’s data to back up Pfizer’s booster shot claims.
Chagla added people “shouldn’t necessarily worry that these two shots are going to be useless in a few years.”
“These are the shots that are going to keep people out of hospital and health care from dying,” he said.
Chagla isn’t alone in his skepticism.
“The general feeling that it is not the right time for a third dose of the mRNA vaccines,” said John Moore, a virologist at Weill Cornell Medicine in New York.
“We’re not saying it should never happen, but now is not the time.”
While there are few studies showing how long protection provided by COVID-19 vaccines lasts, the early research is promising.
A study published in the journal Nature in late June found mRNA-based vaccines create a more “persistent” germinal centre B cell response, which means that a person’s immune response to the jab is stronger and longer-lasting.
The researchers examined participants four months after they received their first Pfizer dose and found that the germinal centres in their lymph nodes, likened to a boot camp for immune cells, kept pumping out said cells to protect against the virus that causes COVID-19.
Despite this research, Pfizer is maintaining that it is “likely” that a third dose “may be needed within 6 to 12 months after full vaccination,” according to the company’s Thursday press release.
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“While protection against severe disease remained high across the full 6 months, a decline in efficacy against symptomatic disease over time and the continued emergence of variants are expected.”
The United States’ FDA and CDC released a joint statement responding to Pfizer’s claims this week — and in it, they said there’s currently no evidence supporting a recommendation of a booster shot.
“Americans who have been fully vaccinated do not need a booster shot at this time. FDA, CDC, and NIH are engaged in a science-based, rigorous process to consider whether or when a booster might be necessary,” the organizations wrote in the statement.
They said this process will look at laboratory data, clinical trial data and, potentially, data from specific pharmaceutical companies — but the research will “not rely on those data exclusively.”
“We continue to review any new data as it becomes available and will keep the public informed. We are prepared for booster doses if and when the science demonstrates that they are needed,” the statement read.
Health Canada struck a similar tone in their own statement about the issue, which they sent to Global News.
“Currently, people who are fully vaccinated are protected from severe disease and death, including from the variants currently circulating,” read the statement.
But Health Canada is open to the possibility of booster shots if the evidence supports it, they said, adding that the longevity of the immune response to existing vaccines is “currently being studied.”
And while Pfizer’s vaccine efforts have been hugely helpful in quashing the spread of COVID-19, they’ve also proven to be extremely lucrative for the company.
In the first three months of 2021 alone, the COVID-19 vaccine raked in $3.5 billion USD ($4.3 billion CAD) in revenue for the pharmaceutical giant, according to their reported first quarter earnings.
Some experts wonder if Pfizer’s arguments in favour of a booster shot could have a financial motivation.
“It’s being (said) that Pfizer is being somewhat opportunistic,” said Moore.
“Pushing the idea of vaccine boosters will, of course, greatly increase vaccine sales.”
Chagla added that these vaccines are some of “the most valuable assets on Earth right now” and that keeping them in the “limelight” likely “plays a role” in what’s happening here.
There may be a need for a booster eventually, Chagla added, but “there is something to be said about the fact that we’re talking about boosters for variants, without a global vaccine plan.”
The threat of vaccine inequality
As for Pfizer’s claims that the “continued emergence of variants are expected,” experts say there’s a much bigger threat when it comes to deadly mutations of the virus: the lack of vaccine coverage around the world.
It comes down to how variants emerge, according to Chagla.
As a virus spreads, it replicates. With each opportunity the virus has to replicate, it has more and more chances to make a mistake. Sometimes, those mistakes end up being advantageous for the virus — either allowing it to spread more easily, or potentially making the virus more severe.
The more COVID-19 spreads, the more opportunities it has to replicate and mutate. That means the biggest risk for the creation of variants is the large pockets of the world where uncontrolled spread is still occurring, Chagla explained.
“The big things that lead to variants are large unvaccinated populations, particularly ones where health systems are really poor and patients with immune conditions,” he said.
And while Canada’s current levels of vaccine coverage are sufficient to stave off the worst outcomes of the pandemic, Moore noted that many countries in the world aren’t so privileged.
“There is an ethical concern about prioritizing dose three for Americans over doses one and two for the rest of the world,” he said.
The WHO has warned that vaccine coverage in some parts of the world remains worryingly low.
“In some parts of the world, the vaccination rates, even at one dose, are one per cent, two per cent, three per cent, five per cent,” said Dr. Peter Singer, an advisor with the WHO, in a Wednesday interview with Global News.
“To be safe is for this fire to be put out everywhere in the world, because otherwise, if it’s burning anywhere, it’s going to be casting off embers that are going to ignite flames everywhere.”
Chagla said that as long as the world prioritizes new variant-focused vaccines over getting those first and second doses rolled out around the world, we’ll all be playing catch-up in preventing COVID-19’s spread.
“We can build vaccines to make ourselves more protected against the evolution of this virus,” Chagla said.
“But if we’re not addressing the root cause of the evolution of this virus, then we’re going to be left with chasing our tails over and over and over again.”
— with files from Global News’ David Lao and Mike Le Couteur
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