I was optimistic that vaccination would halt the spread of the virus—I was wrong.
Dr. Vinay Prasad is a pro-infection, anti-vaccine doctor who has spread copious misinformation about measures to limit COVID, particularly with regards to children. He’s treated vaccine side effects as a fate worse than death, and vaccines experts say his musings on the topic “are based on a litany of false premises and cherry picked information.” A lot of people rightfully don’t trust him, and having heard what he’s said, they don’t want to hear any more.
Yet, in an article from October 2023 titled Why Was My Talk at a Medical Conference Canceled?, Dr. Prasad was eager to portray himself as someone who invites criticism, despite blocking every critic on social media. There’s even a hashtag- #BlockedByVinay. However, Dr. Prasad said that he was a scientist who could change his mind and admit error. He wrote:
I invite my critics to disagree with me on any of my positions and to change my mind. Like any good scientist, I have changed my mind over the course of Covid… I was optimistic that vaccination would halt the spread of the virus—I was wrong.
Though transmission was not an outcome in the randomized-controlled trials (RCTs) of the vaccines, many people were optimistic that they would halt the spread of the virus in early 2021. Indeed, that’s exactly what I said in April 2021:
I’m very very optimistic vaccines will cut transmission of disease. I’m not certain of it. This is why I wear a mask still in public and when treating covid patients.
There’s an infinitesimally low probability of even having an infection that can be detected on a PCR test, let alone being able to spread it to someone.
However, Dr. Prasad did not share my cautious optimism. He sounded quite differently at the time. Although the vaccines and virus were both brand new, he expressed great confidence that vaccines would tame the pandemic and perfectly protect vulnerable people. For example, on February 16, 2021 he said:
We know the vaccine is 100% effective against protecting against bad outcomes for grandparent. (Author note: this was false at the time).
Then on May 13, 2021 he said:
For somebody who’s already been fully vaccinated, they can wear the mask out of solidarity or in a symbolic sense, but their wearing a mask indoors is not benefiting anyone else. There’s an infinitesimally low probability of even having an infection that can be detected on a PCR test, let alone being able to spread it to someone.
However, I find the exchange below to be the most interesting.
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It is highly likely that receipt of vaccination and a 14-day asymptomatic period afterward results in both personal protection and reduced likelihood of ongoing viral propagation.
Let’s be clear what was happened here. Dr. Prasad scolded the “media” and used a laughing emoji to mock those who expressed “bizarre pessimism” that vaccines slowed transmission. When Dr. Jeremy Faust asked for “actual data before guessing”, Dr. Prasad said this was “irrationally pessimistic to say ‘I don’t know’” because the pre-test probability was exceedingly high that a vaccine that prevented SARS-CoV-2 infection would also slow SARS-CoV-2 transmission. Dr. Prasad then linked to an article of his from January 2021, just one month after vaccine campaigns started, titled Throw Away Your Mask After COVID Vaccination? in which he said:
The truth is I wear a cloth mask and I quite like it.
However, even though he liked his cloth mask, he felt vaccines rendered it unnecessary. He said:
The efficacy of the two mRNA vaccines is superb, offering 95% reduction in the rate of acquisition of symptomatic COVID-19 in randomized trials. That is a remarkable result. But the key statistic here is one step beyond the vaccine efficacy. If you get two doses of the vaccine, and if you remain asymptomatic 14 days after the second dose, what is the probability you will develop COVID-19? For Moderna, the answer is there is a 99.92% chance that you won’t….
That risk is in part driven by symptomatic infections which are exceedingly rare after second doses. Risk of spreading is diminished by the brisk immune response that occurs after symptomatic infection once someone is vaccinated… In short, it is highly likely that receipt of vaccination and a 14-day asymptomatic period afterward results in both personal protection and reduced likelihood of ongoing viral propagation…
People need to know that there is light at the end of the tunnel because there is.
Of course, Dr. Prasad didn’t present any actual data that the vaccines impacted transmission, just an argument that because the vaccine prevented SARS-CoV-2 infection, it was therefore highly-likely that it would reduce transmission. Although the vaccine RCTs didn’t assess transmission, he nonetheless felt justified making a reasonable inference. He said in essence, “Sure, we don’t have RCT-level evidence, but it’s OK so use some common sense.”
Fair enough.
Indeed, it was highly likely that if a vaccine prevented SARS-CoV-2 infections, it would also limit the spread of SARS-CoV-2. Unlike most of his pandemic punditry, Dr. Prasad wasn’t entirely wrong here. Although a vaccinated person obviously doesn’t have an “infinitesimally low probability” of transmitting the virus as Dr. Prasad claimed, the vaccine’s impact on transmission has never been zero. It’s always been safer to be around vaccinated rather than unvaccinated people. Of course, everything we know about this comes from observational studies, not RCTs.
However, it was also reasonable for Dr. Faust and myself to take a medically conservative approach in early 2021. Like Dr. Prasad, we were very confident the vaccine slowed transmission. We all agreed that it was OK to use common sense, that we didn’t need an RCT to believe reasonable things. But given what we’d seen the virus do in its first year and that the vaccines were brand new, we also didn’t want to spike the football too early. It wasn’t wrong to wait for more time and actual data to emerge before joining Dr. Prasad in declaring the vaccines were a near-perfect panacea against severe disease and viral transmission.
We all know what happened next.
The company never ran an adequately powered RCT
The evidence supporting the pediatric vaccine today is much more robust than the “evidence” that vaccines prevented transmission in January 2021.
There were 6 successful RCTs of the pediatric COVID vaccine involving nearly 25,000 children. One of them found “the observed vaccine efficacy was 100%.” Many observational studies have since shown its benefit, particularly at preventing rare, but grave outcomes. Yet, Dr. Prasad rejects it all. He has an entirely different standard of evidence.
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Indeed, Dr. Prasad is not willing to say that was highly likely that if a vaccine prevented SARS-CoV-2 infections in children, it would also limit rare, but grave outcomes from SARS-CoV-2. He claims this is an absurd position, and is full of vitriol for those who believe it, calling them “idiots“. He no longer says it’s “irrationally pessimistic to say ‘I don’t know’“. The pre-test probability gets thrown in the trash.
Instead, Dr. Prasad, who has never advanced an actual RCT as far as I know, claims the “the company never ran an adequately powered RCT”. For Dr. Prasad, the RCTs were too small and the observational studies, at least those that support the, vaccine are all fatally “confounded”. He casually dismisses literally every study that supports the pediatric COVID vaccine- several dozen of them– and claims we have no idea whether or not it kept kids safe and out of the hospital.
So what changed? Why was Dr. Prasad willing to make a reasonable inference when it came to the vaccine’s impact on transmission, but not on its ability to limit severe disease in children. Did he completely and abruptly revamp his approach to evaluating medical evidence?
Of course not.
In early 2021, Dr. Prasad wanted vaccines to stop the pandemic and so he did not require an RCT, or any data at all, before claiming they prevented transmission. In contrast, Dr. Prasad strenuously argued that unvaccinated children should contract COVID, even months before there was a pediatric COVID vaccine, and so he does not want the vaccine to benefit children. That would force him to confront an unpleasant thought- doctors’ efforts to purposefully infect unvaccinated children had tragic consequences for some of them.
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To avoid this discomfort, not only does Dr. Prasad have an entirely different standard of evidence for pediatric vaccines, he also has an impossibly high standard. He claims that only an RCT of many thousands of children, which would have to be repeated from scratch for every variant or tweak to the vaccine, could demonstrate its value. Of course, by the time such a massive RCT could be completed, Dr. Prasad would then claim it was obsolete. Though Dr. Prasad said that he “invites critics to disagree with me on any of my positions and to change my mind“, like the old anti-vaxx gimmick of demanding an RCT of the entire vaccine schedule, he’s conveniently set it up so that the only evidence that could change his mind is unobtainable evidence.
More than this, Dr. Prasad makes an additional leap and claims that absent pristine evidence from massive RCTs, the default should be not use the vaccine and to let unvaccinated children contract a potentially fatal virus, the exact opposite of it’s “irrationally pessimistic to say ‘I don’t know’“. He is much more concerned by the possibility of a child receiving a vaccine they don’t need, than by the possibility of a child missing out on a vaccine they do need.
Of course, when observational studies, even a VAERS dumpster dive, purport to show the vaccine’s imperfections, Dr. Prasad lauds them as a “bombshell.” Again, this is because Dr. Prasad accepts or rejects studies based on their results, not their methods, and he wants these studies to be true.
It was abundantly clear that the vaccines trials did not include transmission as a primary or secondary endpoint. And thus could not comment.
Today, Dr. Prasad, a master of creating medical reversals, says, “it was abundantly clear that the vaccines trials did not include transmission as a primary or secondary endpoint. And thus could not comment,” and he calls for investigations into those who said what exactly what he said in 2021. So the next time he merely “calls for” an RCT of this or that, ask yourself if he’s applying his standards of evidence consistently, or if he’s again saying “RCTs for thee, but not for me” because his goal is minimize COVID and to sow mistrust, not advance actual medical research.
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And while admitting error is never easy and should always be applauded, the first step is to honestly admit error. Dr. Prasad didn’t express optimism that the vaccine would halt the spread of the virus, he expressed certainty. If Dr. Prasad ever chooses to “admit” error again, I suggest he share this Tweet from February 18, 2021:
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If Dr. Prasad has the integrity to actually share his own words, his readers will know exactly what he was wrong about. They will also know that for the past three years he’s said anyone who disagreed with his COVID minimization was “completely off, and just another squeeze of fear.”
Nearly 700,000 Americans have since died of COVID since Dr. Prasad said that. Sadly, these “fear mongers” were right much more often than him.
And today, many of them don’t want to hear Dr. Prasad, not because they’re afraid of his oh-so controversial opinions, but rather because they see no value in being subjected to his mocking misinformation. They know he has inconsistent and contradictory standards of evidence based on what he does and does not want to be true. They’d rather listen to someone who is willing to adjust their ideology to match the data, rather than to someone who transparently massages the data to suit his ideology.
Can you blame them?