The CDC press release you link to is misinformation. Its title is "New CDC Study: Vaccination Offers Higher Protection than Previous COVID-19 Infection". But that is not what the study demonstrates. It demonstrates instead that getting vaccinated in addition to having had COVID-19 previously improves immunity. It does not demonstrate that people who are only vaccinated (not previously infected) have higher immunity than people who were prevously infected (and not vaccinated).

I completely agree with all of that. The press release is misleading, it was probably drafted in bad faith with the intent to mislead, and its title as stated is factually inaccurate and directly contradicts the balance of the available evidence from other research. I condemn all of that.

However, it's worth emphasizing that none of that invalidates the parent commenter's claim that vaccination provides significant additional protection against reinfection for people who've already had COVID, as the study linked in the press release finds.

CDC has tainted epidemiological data by issuing guidance to exempt vaccinated people from testing unless symptomatic. Vaccinated asymptomatic cases were simply not counted for a period of time ending in late June 2021. I can't find the date when they issued the faulty guidance for a precise time interval, but any study comparing vaccinated / unvaccinated cases relying on US epidemiological data including May/June 2021 must sadly be considered tainted.

https://www.nytimes.com/live/2021/07/28/world/covid-delta-va...

It’s hardly hiding what’s being described, the very first sentence clarifies: In today’s MMWR, a study of COVID-19 infections in Kentucky among people who were previously infected with SAR-CoV-2 shows that unvaccinated individuals are more than twice as likely to be reinfected with COVID-19 than those who were fully vaccinated after initially contracting the virus.

As to which is better, there are studies showing higher protection from vaccination alone than prior infection, and other showing the opposite. It’s complicated in part because the pandemic has been around for significant periods so the timing of infection vs vaccination matters. Further, infection doesn’t provide a uniform level of protection and of course the details get deep. https://www.cell.com/cell/fulltext/S0092-8674(20)31235-6?_re...

And of course from a public health standpoint a positive Covid test isn’t guaranteed to represent an actual infection.

> there are studies showing higher protection from vaccination alone than prior infection, and other showing the opposite.

So you admit to listing one small study that states A while knowingly ignoring the other studies that argue the opposite? The NIH-funded study and Israel’s data are relevant counterpoints in this discussion.

It’s not just one small study for example here’s: Not all persons recovering from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection develop SARS-CoV-2–specific antibodies. https://wwwnc.cdc.gov/eid/article/27/9/21-1042_article

I granted severe infections do result in a strong immune response, but simply having a positive test result isn’t the sign of long term immunity people assume. That said, surviving COVID also implies a healthy immune system which is a rather morbid example of survivorship bias.

> but simply having a positive test result isn’t the sign of long term immunity people assume

You were overly dismissive in your first mention of this. Do you have data behind the tests being false positive? Multiple positive tests + symptoms are surely sufficient

That really depends on the tests and time period. False positive rates depend not just in the test but also the percentage of population infected. Unfortunately many people where diagnosed based on symptoms or a single test which was inaccurate. At the time telling someone to self isolate based on an inaccurate test and only preforming more accurate testing if they got really sick was considered acceptable.

In a study of 14 of the approved tests, one of the tests gave false positives more than 15% of the time, and three others gave false positives more than 10% of the time. https://www.sfgate.com/coronavirus/article/which-COVID-19-te...

Is this a joke? CDC issues guidance that vaccinated persons should not get tested anymore unless symptomatic, then collects data showing that, lo and behold, vaccinated people have lower rates of reinfection. Duh, you just stopped measuring infection rates for vaccinated asymptomatic cases, which are the majority of covid infections.

You'd think that CDC employees would disclose CDC guidance that might be invalidating the core premise of their study... Consider finding an alternative to CDC. FWIW, UK has pretty good data.

> This report details the findings of a case-control evaluation of the association between vaccination and SARS-CoV-2 reinfection in Kentucky during May–June 2021 [...] Second, persons who have been vaccinated are possibly less likely to get tested. Therefore, the association of reinfection and lack of vaccination might be overestimated.

https://www.cdc.gov/mmwr/volumes/70/wr/mm7032e1.htm

> July 28, 2021. Anyone who has been potentially exposed to the virus should get tested, the C.D.C. now says. Previous guidance recommended testing only for fully vaccinated people who were symptomatic.

https://www.nytimes.com/live/2021/07/28/world/covid-delta-va...

That was controlled for in the study because these people aren’t idiots.

If you really don’t trust US data there is another study out of Israel again showing a single vaccine dose after infection significantly reduces reinfection risks.

Unless there is a technical explanation on how exactly the study 'controlled' for the data bias they failed to disclose, the study is tainted, sorry. This is a technical audience, we can double check the math. They should retract it, but this is 2021 US with too much politics everywhere, so probably they won't.

The substantive discussion is a separate topic. Given all the facts we know so far, including exponential antibody decay and the obvious need for boosters, looks like the vaccines temporarily raise the antibody levels, and then peter out. Note, I'm not making any claims which immune system stimulus is better long term, vaccines or covid infection. We simply don't understand the long term interplay of the human immune system, the vaccines and the virus. Short term studies amount to 'we put a drop of ink into the ocean, measured the water color 1 second later, yay, the ocean is now black'. Hard to credibly extrapolate them 20 years in the future.

So far we assumed a static virus. The largest risk with the current vaccination campaign is that it is using a monoculture vaccine, teaching the immune system to eliminate a grand total of 1 protein. Even a cursory familiarity with how evolution works in large monoculture populations should raise some red flags. https://www.canr.msu.edu/grapes/integrated_pest_management/h.... Long term the virus is likely to figure out a way to do its thing while escaping the vaccine protection. (It so happens that Pfizer CEO publicly agrees with this position, so there).

Given that it is fundamentally impossible to predict the long term evolution of the pandemic absent a time machine, it is highly unethical to force people take the vaccine using universally reviled tactics like state enforced segregation and discrimination.

(Disclaimer: I am vaccinated and hope for the best).

> exponential antibody decay

Antibodies are part of the adaptive immune system but are only produced when the body thinks there is an active infection. To simply greatly long term immunity is maintained via memory B cells because constantly producing antibodies to every disease encountered is untenable. https://en.wikipedia.org/wiki/Memory_B_cell

> grand total of 1 protein

That’s not how these vaccines work. A vaccination covers a huge range of mutations in that spike protein as the immune system memorizes multiple targets. Again simplifying it’s like memorizing 4 of your ten fingerprints, lose a finger and you still match the other 3. The protein target is chosen because it is part of the mechanism of infection, without that a simple COVID variant can’t infect you. Of course given enough time it could evolve around this issue but we are not talking about a single mutation.

> A vaccination covers a huge range of mutations in that spike protein as the immune system memorizes multiple targets.

This is an excellent technical point. Trouble is we already know that we are 'a few mutations away' from a covid variant evading vaccines, which is 'likely' to emerge. A recent Japanese preprint nailed it down to just 4: K417N, N439K, E484K and N501Y.

https://www.deseret.com/coronavirus/2021/8/26/22642809/delta...

https://www.biorxiv.org/content/10.1101/2021.08.22.457114v1

Rachel Walensky, CDC boss, July 2021: "the largest concern that we in public health and science are worried about is that the virus…[becomes] a very transmissible virus that has the potential to evade our vaccines in terms of how it protects us from severe disease and death". A new, more elusive variant could be "just a few mutations away," she said.

https://www.webmd.com/vaccines/covid-19-vaccine/news/2021073...

Albert Bourla, Pfizer CEO, Aug 2021: "Every time that a variant appears in the world, our scientists are getting their hands around it. And they are researching to see if this variant can escape the protection of our vaccine. We haven't identified any yet, but we believe that it is likely that one day, one of them will emerge."

https://www.insider.com/pfizer-ceo-vaccine-resistant-coronav...

Nature, March 2021: "Our study and the new clinical trial data show that the virus is traveling in a direction that is causing it to escape from our current vaccines and therapies that are directed against the viral spike,” says Ho, the director of the Aaron Diamond AIDS Research Center and the Clyde’56 and Helen Wu Professor of Medicine at Columbia University Vagelos College of Physicians and Surgeons.

https://www.cuimc.columbia.edu/news/new-study-coronavirus-va...

https://www.nature.com/articles/s41586-021-03398-2

=====

> long term immunity is maintained via memory B cells because constantly producing antibodies to every disease encountered is untenable

You are reading this backwards. I am not making any claims of what the appropriate level of antibodies ought be for long term immunity. I find "using tainted data we found 2x increase of antibody levels in post-infection + vax compared to just post-infection" studies ridiculous. The people pushing vaccines on people with prior infection, the people pushing boosters, the cottage industry of antigen studies making bold immunity extrapolations are making such claims. Perhaps you should spend some time educating them of basic immune system functions?

I wouldn't mind that much, everybody is free to chose their own risk profile. Right? Then they throw away the democratic norms and practices of past 200 years because they don't get the buyin levels (100%) they were hoping for. That is evil.

People may want to read the section of that study in terms of its limitations. Holy shit.

” The findings in this report are subject to at least five limitations. First, reinfection was not confirmed through whole genome sequencing, which would be necessary to definitively prove that the reinfection was caused from a distinct virus relative to the first infection.…”

That wouldn't significantly affect the conclusion though, right? They compared the reinfection rate for people with previous infection + vaccine to people with previous infection + no vaccine. Since both groups previously had COVID, shouldn't that cause (in expectation) the same false positive rate for both groups when testing for reinfection?

Edited to add: The authors cite [0] to support their claim that it's not significant, it basically seems consistent with their claim that it's really unlikely to still have viral shedding at the duration that they tested at.

Also worth mentioning that adding an equal proportion of false positives to both groups would cause the study to understate the effect size (i.e. the magnitude of the additional protection conferred by vaccines) by biasing the odds ratio in the direction of 1.

[0] https://www.thelancet.com/journals/lanmic/article/PIIS2666-5...

Ok. mRNAs are evaluated to have an efficacy of ~95%; J&J (adenovirus) at 67%. Are then the J&J recipients mandated to get an mRNA too, so that they not get infected at higher rates than their mRNA recipients?

Pfizer was recently downgraded to 39% efficacy after a few months: https://link.springer.com/article/10.1007/s10654-021-00808-7. So unless you'd like IaaS to mean "immunity as a service" and pay Pfizer in perpetuity every 3 months or so, vaccines merely prepare you to tolerate the real thing a little better making this novel virus not so novel. You can't "stop covid" with them, and why the authorities continue to lie about this, I can't even fathom at this point.

Not to put too fine a point on this, but make no mistake, vaccine or no vaccine, you _will_ get COVID. You'll just be 10x less likely to die from it, although that's being called into question as well by now. Be that as it may if you're on the older side and/or obese, you should get vaccinated if you haven't had COVID yet. I did. I've also lost 15 kilos so far, and I don't intend to take any "boosters".

Sure, getting vaccinated after one recovers from an infection imparts the highest level of protection by that wasn't the GP's point. A prior infection imparts a much higher level of protection against future infections than any vaccine that we currently have.

Possibly, though positive Covid tests aren’t a guarantee of an actual infection which might be why some studies showed vaccination was more effective.

Alternatively, having survived the first infection says more about the individual than getting a vaccination. Which is yet another way this stuff gets tricky.

> some studies showed vaccination was more effective

Could you point me to them? I'm unable to find any.

Here’s one showing prior infections or at least prior positive test results failing to result in long term immunity.

https://wwwnc.cdc.gov/eid/article/27/9/21-1042_article

The linked article does not study long term reinfection rates, it studies systemic antibody response. Unfortunately, the topic of long-term covid antibody research is a difficult area: both exponential antibody decay and antibody location are relevant. Extrapolating epidemiological conclusions from small population antibody studies is reaching.

Population studies run into different issues you want both. I recall an early study showing vaccination being significantly more effective, but that’s before current variants showed up etc.

Really you can’t draw accurate conclusions from any one study but multiple studies give you a better picture of what’s going on. Large numbers of people falsely believe they had COVID, people who survived COVID are healthier than the general population because the other option is death, the most common infection doesn’t get a strong immune response, vaccine recipients tend to be older and in worse health etc.

That said, an otherwise healthy person who got very sick from COVID and got multiple high quality tests verifying exposure likely does have a significantly better long term protection. But, that’s not representative of the general population that had COVID.

Andrew Gelman has a blog post about this misleading report: https://statmodeling.stat.columbia.edu/2021/10/01/cdc-as-bad...

He’s just complaining about the title as misleading when the very first sentence provides full clarification.

However even the other interpretation is supported by evidence like this. https://wwwnc.cdc.gov/eid/article/27/9/21-1042_article Though critically surviving COVID says good things about the immune system even if you didn’t develop an immunity you may still be better off than the average vaccination recipient who tends to be older and in worse health. Which further confuses the issue at the population level.