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Evaluating necessity of Covid-19 vaccination in previously infected individuals

medrxiv.org

11–20 of 361 posts

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#11
I did have covid (not diagnosed while active but shown in antibody test), and I got vaccinated significantly later. This was not driven by belief in medical need, but by social/rules need. You get no "points" for being recovered like you do for a proof of vaccination.

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#12
post #8

Note this is to inform public health / prioritization in the short term. (Which is less necessary places like the US where there is excess vaccine supply). We know that past infection greatly reduces risk (and this helps quantify it). At the same time, vaccination is thought to cause a much broader and more durable immune response than natural infection. We'd like people who were previously infected to get vaccinated…

Not that I have any knowledge on this subject, but why would a vaccine that stimulates the creation of a bit of spike protein create a "much broader and more durable immune response" than the actual virus which I presume creates a hell of a lot more of that exact same spike protein? Genuinely curious, because my simpleton assumption would be the opposite.

Also no knowledge on the subject, but I can image a case where it is more durable:

If the spike protein is absolutely critical to the virus, but can't change too much without affecting function, an immune response that is specifically targetted against it would be better than an immune response against any other protein that could change without affecting the function.

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#13

Punchline: “The cumulative incidence of SARS-CoV-2 infection remained almost zero among previously infected unvaccinated subjects, previously infected subjects who were vaccinated, and previously uninfected subjects who were vaccinated, compared with a steady increase in cumulative incidence among previously uninfected subjects who remained unvaccinated. Not one of the 1359 previously infected subjects who remained u…

In that case it seems like the headline reads wrong based on a colloquial and imprecise but often correct heuristic. Should read more like "non-necessity of C19 vaccination for previously infected..."

But that wouldn't contribute with the propaganda of the current mainstream narrative, would it?

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#14
post #9
post #8

Note this is to inform public health / prioritization in the short term. (Which is less necessary places like the US where there is excess vaccine supply). We know that past infection greatly reduces risk (and this helps quantify it). At the same time, vaccination is thought to cause a much broader and more durable immune response than natural infection. We'd like people who were previously infected to get vaccinated…

> vaccination is thought to cause a much broader and more durable immune response than natural infection Why? Is there any data to support this assertion? If anything, being ill (symptomatic) means the viral load was high in the body, so the immune system response should be as well, and in addition, infection should cause the immune system to produce antibodies to all parts of the virus, not just the spike protein, a…

"it is thought" I guess comes from nonsense like this: https://www.huffingtonpost.co.uk/entry/does-the-vaccine-give...

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#15
post #8

Note this is to inform public health / prioritization in the short term. (Which is less necessary places like the US where there is excess vaccine supply). We know that past infection greatly reduces risk (and this helps quantify it). At the same time, vaccination is thought to cause a much broader and more durable immune response than natural infection. We'd like people who were previously infected to get vaccinated…

Not that I have any knowledge on this subject, but why would a vaccine that stimulates the creation of a bit of spike protein create a "much broader and more durable immune response" than the actual virus which I presume creates a hell of a lot more of that exact same spike protein? Genuinely curious, because my simpleton assumption would be the opposite.

My mental model of this (and I'm not a medical expert) is that (a) for a given amount of spike protein, the immune response is similar, whether the protein originates from the vaccine or the actual virus, but (b) since the vaccine is lacking the actual health threatening properties of the virus, you can expose people to massive doses of it without incurring much risk.

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#16

Punchline: “The cumulative incidence of SARS-CoV-2 infection remained almost zero among previously infected unvaccinated subjects, previously infected subjects who were vaccinated, and previously uninfected subjects who were vaccinated, compared with a steady increase in cumulative incidence among previously uninfected subjects who remained unvaccinated. Not one of the 1359 previously infected subjects who remained u…

However there already exist real people in the world who have had Covid twice, and who reportedly have had a much tougher time the second time around.

This study helps us put some bounds on how many people this might happen to (assuming there are no mutations to the virus) but it doesn't rule it out completely, because of the prior existence proofs

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#17
post #8

Note this is to inform public health / prioritization in the short term. (Which is less necessary places like the US where there is excess vaccine supply). We know that past infection greatly reduces risk (and this helps quantify it). At the same time, vaccination is thought to cause a much broader and more durable immune response than natural infection. We'd like people who were previously infected to get vaccinated…

Not that I have any knowledge on this subject, but why would a vaccine that stimulates the creation of a bit of spike protein create a "much broader and more durable immune response" than the actual virus which I presume creates a hell of a lot more of that exact same spike protein? Genuinely curious, because my simpleton assumption would be the opposite.

The rough theory - as I understand it - is that the virus is composed of other things as well as the spike protein e.g. the proteins in the viral shell. The immune system can learn to attack _whatever_ foreign materials it encounters. So a person that clears the infection might have a strong immune response to the spike protein, but the response could also be focused on some other part of the virus (or a mixture of different viral features).

Problem is, the "some other part" can mutate more easily into a form that the immune system no longer recognizes than the spike protein can, because the spike protein has to keep its form in order to react with the ACE2 receptors and enter a human cell. So the concern isn't that a real infection doesn't leave you immune to the virus you got sick with, but that the immunity might not apply or be as robust against a variant where the "some other part" has mutated into a different form.

The mRNA vaccines only cause your cells to make the (difficult to significantly mutate) spike protein, so the expectation is that vaccinated people would have a robust immune response against any variants which have that spike protein, regardless of whatever else changed, and a variant with an unrecognizable mutation of the spike protein would be less infectious anyway, as it could no longer successfully enter human cells either.

The results of the paper seem to indicate that this is not a problem in practice (so far - new variants are still evolving), but it's nice that someone checked.

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#18
post #8

Note this is to inform public health / prioritization in the short term. (Which is less necessary places like the US where there is excess vaccine supply). We know that past infection greatly reduces risk (and this helps quantify it). At the same time, vaccination is thought to cause a much broader and more durable immune response than natural infection. We'd like people who were previously infected to get vaccinated…

Not that I have any knowledge on this subject, but why would a vaccine that stimulates the creation of a bit of spike protein create a "much broader and more durable immune response" than the actual virus which I presume creates a hell of a lot more of that exact same spike protein? Genuinely curious, because my simpleton assumption would be the opposite.

The mRNA vaccines (among others) include adjuvants that enhances the immune response.

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#19
post #16

Punchline: “The cumulative incidence of SARS-CoV-2 infection remained almost zero among previously infected unvaccinated subjects, previously infected subjects who were vaccinated, and previously uninfected subjects who were vaccinated, compared with a steady increase in cumulative incidence among previously uninfected subjects who remained unvaccinated. Not one of the 1359 previously infected subjects who remained u…

However there already exist real people in the world who have had Covid twice, and who reportedly have had a much tougher time the second time around. This study helps us put some bounds on how many people this might happen to (assuming there are no mutations to the virus) but it doesn't rule it out completely, because of the prior existence proofs

If this is rare enough, it could fall into the false positive rate of the COVID test they've previously done (i.e. while the test said they had COVID, they didn't)

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#20

I did have covid (not diagnosed while active but shown in antibody test), and I got vaccinated significantly later. This was not driven by belief in medical need, but by social/rules need. You get no "points" for being recovered like you do for a proof of vaccination.

Sounds uncomfortably like coercion...
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