[HN Gopher] Evaluating necessity of Covid-19 vaccination in prev...
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Evaluating necessity of Covid-19 vaccination in previously infected
individuals
Author : bananapizza
Score : 50 points
Date : 2021-06-09 21:50 UTC (1 hours ago)
(HTM) web link (www.medrxiv.org)
(TXT) w3m dump (www.medrxiv.org)
| trimbo wrote:
| I have confirmation bias here because this is a result I would
| have expected BUT..
|
| Preprint, non-peer reviewed.
| epgui wrote:
| Any other result would have been surprising. Why is this
| interesting, beyond just confirming what we were already 99.99%
| certain we knew?
|
| -- biochemist
| StavrosK wrote:
| It's just nice for us laymen to have more confirmation.
| symlinkk wrote:
| Because openly stating this obvious fact would get you
| downvoted on here a few months ago.
| OJFord wrote:
| Because it's not public health policy anywhere that I'm aware
| of? But vaccine rollout would be way quicker, and 'positive
| test or vaccinated' proportion of populations would be way
| higher, and that would influence discussion of other aspects,
| like 'herd immunity' for example.
| mlyle wrote:
| 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 _eventually_ for these benefits, but they 're not who
| you'd want to vaccinate _first_.
| tomp wrote:
| _> 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, as with mRNA vaccines.
| akomtu wrote:
| If there was evidence, that "is thought to" would've been
| replaced with "is proven to".
| jjgreen wrote:
| "it is thought" I guess comes from nonsense like this:
| https://www.huffingtonpost.co.uk/entry/does-the-vaccine-
| give...
| mikedilger wrote:
| 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.
| variaga wrote:
| 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.
| jdavis703 wrote:
| The mRNA vaccines (among others) include adjuvants that
| enhances the immune response.
| maxerickson wrote:
| No, they don't. The lipid nanoparticles they use seem to
| have an adjuvant effect, but they are also directly
| functional, and there's not anything else in the mRNA
| vaccines.
| maxerickson wrote:
| It's not entirely the same. The Pfizer, Moderna and J&J (and
| Novavax) vaccines adjusted the protein to present a more
| consistent target than the viral spikes:
|
| https://cen.acs.org/pharmaceuticals/vaccines/tiny-tweak-
| behi...
| sdflhasjd wrote:
| 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.
| microtherion wrote:
| 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.
| rolph wrote:
| the problem with live covid as the antigenic character is of
| course the mortality, and the morbidity risk.
|
| there is also the instability of the spike protien in its natural
| form. when spike is cloven at it cleavage site it changes
| conformation, thus there are two faces available to the immune
| system; the default state, the cloven prefusion state. This makes
| a Naturally aquired immunity biased toward opsonizing antbodies.
|
| the vaccine version of spike has been stabilized so as to remain
| in the default state resulting in a bias toward neutralizing
| antibodies.
|
| so neutralizing antibodies bind to the viral spike at locations
| that interfere with receptor docking thus ideally preventing
| viral entry, while the immune system operates upon the many other
| viral epitopes, to produce a variant array of antibodies. This
| gives Tcell based [longterm] immunity.
|
| the naturally aquired immunity involves Tcell activity upon
| infection, but that is the risk, as virus is capable of entering
| the cells before immune system begins to work against it.
|
| this is why boosting is required beyond initial vaccine dose.
|
| and this is why i believe it would be a good idea to take a
| vaccine along with naturally aquired immunity due to recovery,
| and you can have the best of both worlds, while not relying
| solely on naturally based immunity.
| StavrosK wrote:
| What's up with all the antivaxxer/COVID hoaxer comments lately?
| Every COVID-related thread seems to be at least half-full of
| antivaxxer comments, and that's being optimistic.
| np_tedious wrote:
| 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.
| joshuahughes wrote:
| Sounds uncomfortably like coercion...
| isaacremuant wrote:
| It is coercion. People have been coerced at every step of
| this crisis, by the threat of police violence, by the threat
| of reputation or job loss, by the the threat of fines and
| more.
|
| Hopefully, like we see with the wuhan lab theory suppression,
| as time goes on, a lot of what people suffered will come to
| light, and be contrasted by the benefit of the elite and
| political class during all this.
| version_five wrote:
| I agree 100% - whatever reaction posts like yours get, it's
| important to realize that a lot of people think this way,
| quite possibly a majority if you could talk to them on
| their own, despite efforts to pretend anyone against
| whatever government / corporate orthodoxy is pushing this
| week is some kind of conspiracy nut
| reducesuffering wrote:
| 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
| unvaccinated had a SARS-CoV-2 infection over the duration of the
| study."
| Taniwha wrote:
| 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
| tomerico wrote:
| 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)
| Taniwha wrote:
| Could be - but the case I remember reading about involved
| hospitalisation.
|
| Remember that immunisation makes antibodies but only
| provides something like 50-95% protection (depending on the
| vaccine) - it's not surprising that actually catching it
| does the same thing
| stickfigure wrote:
| Health policy is determined by probabilities, not
| possibilities.
| version_five wrote:
| Health policy (not uniquely) is determined in large measure
| by politics.
| stephc_int13 wrote:
| I got covid twice.
|
| 10 months separated the first and the second infections.
|
| Both were mild, the second was worse (English variant).
| onionisafruit wrote:
| Now I know two things about you: 1. you got covid twice 2.
| you weren't part of this study
| msandford wrote:
| 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..."
| OJFord wrote:
| It says (at least, it does now, as I write) ' _evaluating_
| necessity '.
|
| Necessity is the concept as well as describing one possible
| state of it.
|
| Another example: when 'my hunger is sated', I do not 'have a
| hunger', I am 'not hungry'.
| sebastianconcpt wrote:
| But that wouldn't contribute with the propaganda of the
| current mainstream narrative, would it?
| pmoriarty wrote:
| _" Not one of the 1359 previously infected subjects who
| remained unvaccinated had a SARS-CoV-2 infection over the
| duration of the study."_
|
| The duration of the study being 5 months.
|
| There's no indication from this study what would happen after 5
| months.
| teachingassist wrote:
| This comment is right - and the study began shortly after
| Ohio's peak of infections.
|
| As such, most infected participants would have been recently
| infected in a situation with low and decreasing virus
| circulation. Nobody thinks there's any risk of reinfection at
| that point.
| StavrosK wrote:
| That's encouraging! I got COVID a few months ago and got
| vaccinated recently, seems like I should be unstoppable now.
| rolph wrote:
| i wouldnot call it unstoppable, but i would expect excellent
| protection, that extends horizontally to provide an
| unspecified degree of protection across variants.
| rolph wrote:
| this is a bit ambiguous in title.
|
| This is about vaccination not providing any further benefit to
| those who have recovered and cleared from covid.
|
| this is ^not^ saying you need to be vaccinated even if you have
| gone through covid
| dang wrote:
| Ok, I've consed an 'evaluating' onto the title above in the
| hope of communicating this.
| rolph wrote:
| thanks dang
| takeda wrote:
| On the other hand this says the opposite:
| https://www.biorxiv.org/content/10.1101/2021.04.15.440089v4?...
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(page generated 2021-06-09 23:00 UTC)