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0 pointscriticaltinker4y ago0 comments

Here is a paper (not yet peer-reviewed) which presents statistically strong evidence (N = 52,238) that vaccinating previously infected individuals provides practically no benefit [1].

Quote from [1]:

- "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."

Right now there is no scientific consensus that full vaccination of previously infected individuals provides any additional protection that is meaningfully beneficial. In fact there is a lot of evidence pointing the other way - supporting the idea that vaccination strategies should be highly targeted at only the most vulnerable populations.

[1] Necessity of COVID-19 vaccination in previously infected individuals https://www.medrxiv.org/content/10.1101/2021.06.01.21258176v...

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3 comments · 1 top-level

raphlinus4y ago· 2 in thread

Thanks for bringing this paper, it's relevant to the conversation. A couple of points of context.

First, this study is quite early on in the vaccination campaign, when supplies were very short. The main conclusion is that they should be prioritized to people who have not had prior infection. That advice was not followed, largely because determining prior infection status complicates the protocols for vaccination quite a bit, and simpler is better. Now, at least in the US, we're in a situation where we are literally throwing vaccine down the drain[1, 2].

Second, this study in particular predates the significant spread of the delta variant, and there is particular concern about reinfection from that variant[3]. Vaccine effectiveness appears to be somewhat reduced compared with the original variant, but still pretty good.

This is definitely an area where more science is needed.

[1]: https://www.statnews.com/2021/07/20/states-are-sitting-on-mi...

[2]: https://www.al.com/coronavirus/2021/08/alabama-threw-out-650...

[3]: https://www.nature.com/articles/s41586-021-03777-9

criticaltinkerOP4y ago

> The main conclusion is that they should be prioritized to people who have not had prior infection

You're leaving out the primary finding, here is the actual conclusion from the study I previously cited [1]:

- "Individuals who have had SARS-CoV-2 infection are unlikely to benefit from COVID-19 vaccination, and vaccines can be safely prioritized to those who have not been infected before."

> this study in particular predates the significant spread of the delta variant, and there is particular concern about reinfection from that variant

I agree on the general point. Relevant to the discussion is the fact that the OP paper addresses this, here are relevant excerpts:

- "Our findings show that most COVID-19 patients induce a wide-ranging immune defense against SARS-CoV-2 infection, encompassing antibodies and memory B cells recognizing both the RBD and other regions of the spike, broadly-specific and polyfunctional CD4+ T cells, and polyfunctional CD8+ T cells."

- "The immune response to natural infection is likely to provide some degree of protective immunity even against SARS-CoV-2 variants because the CD4+ and CD8+ T cell epitopes will likely be conserved."

- "Thus, vaccine induction of CD8+ T cells to more conserved antigens such as the nucleocapsid, rather than just to SARS-CoV-2 spike antigens, may add benefit to more rapid containment of infection as SARS-CoV-2 variants overtake the prevailing strains."

These findings hint that naturally acquired immunity may actually be more robust to variants of concern in comparison to the immune response induced by vaccination. But admittedly this has not been proven yet.

See my top level post on this thread for more details and citations.

spfzero4y ago

Thanks, that was what I keyed into reading the OP as well.

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