Vaccine question

Polio vaccines were given multiple times (different varieties) over a number of years.

If I’m not mistaken, we’ve got a nationwide (worldwide?) trial going on right now. I’m not going to blame you if you don’t want to participate. But we will have a ton of data about multiple boosters over a short time pretty soon. I strongly suspect the data will show it is safe. If it weren’t, we’d be having a whole bunch of reports of problems. But we don’t, so I suspect it’s safe. The question will be effectiveness.


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I agree that the boosters are almost certainly safe and probably have at least a marginal benefit in reducing Covid symptoms. But I think most everyone in the field agrees that the science behind the boosters is messy and difficult to intrepret. The only way to get a conclusive answer is through a randomized clinical trial, and I don’t believe that is being done. If you are really interested in this topic you should read this Vox article from a couple of days ago.

One excerpt relevant to this thread states:

There’s also some concern that giving people updated boosters too frequently reduces their impact. Scientists increasingly suspect that the first strain of a germ one’s body encounters (whether from infection or vaccination) provides the most durable immunity. New research suggests that when later variants of the same germ come along too quickly, the immune system does not mount as robust a response targeted against them. This phenomenon is called “imprinting,” and it may mean diminishing immunological returns for boosters that are updated too often.

That seems to be consistent with what the mouse study showed and why a few linked data sets on this thread show more infections with higher number of vaccinations. Not sure why everyone here seems to feel that such data is bogus.


You’d need to take that up with your Straw Man.

Unless I’m getting punchy this far into the thread, the general thrust of most responses has been that an apparent reduction in efficacy of recurrent vaccination might not be the counterintuitive phenom implied/imagined in the initial pre print. Along with a bit of misplaced nostalgia regarding good old vaccines like we had with smallpox, right?

Nothing bogus…just suggestions that, with sufficient and adequate peer review, the original authors’ conclusions may well not match their hypothesis …with tentative explanations as to why.

Your Vox article is a little messy to understand but the full article isn’t quite as succinct at implying lack of efficacy as your snippet suggests. It read pretty unequivocally that it’s served at least the older community well in reducing severity of symptoms.

The explanation of “imprinting” is really just a straightforward description of why a vaccine that’s effective against an initial strain of a virus doesn’t necessarily protect against subsequent and different variants that occur with a rapidly evolving virus (which SARS-COV-2 is) It’s disappointing, for sure, but blame the virus…it too is playing Whac-A-Mole.

Isn’t what we are likely to see is a new vaccine every year adapted to any new strains that have emerged and become dominant … just like flu?


Much more fun: How about vaccines for the common cold?

Why…you don’t imagine that flu is little more than the common cold, surely (although flu vaccines have been a target of the anti-vaxxers and sundry nitwittery)

Yes it is being done. I know because a couple I know were in the initial trials for the first Pfizer vaccine. They both got the real shot, revealed later to them. Again, they were in the new booster trials early(?) last year and one got the real shot and the other didn’t, revealed later and the placebo person immediately got the real shot the week they came out. Both are 65+ with one having had cancer a few years ago and other problems, the other pretty healthy and an avid hiker.


No offense, but when it comes to issues on health you probably shouldn’t comment on stuff you don’t understand. Someone might actually believe you and hurt themselves.

Imprinting with respect to Covid is the observation that boosters specific for Covid variants turn out to be no more effective at preventing infection than the original vaccine. Suppose the original vaccine has epitope V-2 and one gets an immune response specific to V-2. Now variant BA4 replaces V-2 in the pandemic so a vaccine specific to BA4 is developed to act as a booster. Turns out that the BA4 booster stimulates a big immune response to V-2, but not much for BA4. That is the phenomenon of imprinting and explains why boosters specific to variants aren’t as effective as predicted.

Here is an editorial in the New England Journal of Medicine that explains this and makes the following recommendation:

“…booster dosing is probably best reserved for the people most likely to need protection against severe disease — specifically, older adults, people with multiple coexisting conditions that put them at high risk for serious illness, and those who are immunocompromised. In the meantime, I believe we should stop trying to prevent all symptomatic infections in healthy, young people by boosting them with vaccines containing mRNA from strains that might disappear a few months later.”

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I don’t doubt that, since the original vaccine didn’t actually induce sterilising immunity ( as I mentioned upstream) This is what would be necessary in order to prevent transmission directly…in the way that, say, the smallpox vaccine did. However (again as I mentioned upstream ) it doesn’t appear to be mandatory in order to contain an epidemic as evidenced by the fact that there are vaccines that demonstrate efficacy against some of the infectious diseases in spite of this that are routinely vaccinated for (outside of anti vaccine circles)…pertussis, for example.

As disappointing as this might be, it certainly does appear to have provided a better benefit for high risk groups than others in reducing the severity of symptoms.

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Monday the FDA outlined it publicly in a set of documents released in advance of a meeting Thursday of the agency’s Vaccine and Related Biological Products Advisory Committee (VRBPAC). The committee will vote on the agency’s proposal.


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