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Antibody levels highly predictive of immune protection from symptomatic Covid

nature.com

31–40 of 77 posts

Re: Antibody levels highly predictive of immune protection from symptomatic Covid

#31
post #2

My father tested negative for spike specific antibodies 2 weeks after the 2nd Pfizer vaccine (he's not the only one), and as I didn't find any data on people who test negative (and I know that the vaccine has 94% efficiency preventing COVID), he's still mostly not leaving his apartment. He'll have a test against the viruses themselves next week, but he'll need to wait 2 weeks for the result for that test.

If the vaccine is truly 95% effective in preventing infection, how did 9 fully vaccinated Yankees players all contract the virus?

Part of it is probably that these people get tested very often.

The "95% protection rate" doesn't really mean people don't get infected. Vaccinated people get in contact with as much virus as others.

What it means is their immune system defeats 95% of the infections before you notice you're sick.

But if you get a test while your body is in the middle of crushing such a small infection, you'll test positive.

Re: Antibody levels highly predictive of immune protection from symptomatic Covid

#32

Earlier quoted context omitted.

I believe the paper indicates otherwise, in regards to immunity. To help make sense of the paper, I read this Science Daily article that reviews it, and contains some comments from the paper's authors. https://www.sciencedaily.com/releases/2021/05/210517105727.h... Here, one of the people associated with the paper mentions: "Vaccination works very well to prevent both symptoms and severe disease in the short to mediu…

So it will become endemic and be one of the common colds ?

pretty much. This what happened with 7 cold viruses and 2* flu viruses. I don't think it's realistic to destroy the virus reservoirs.

*not sure if these are the exact number I remember from the lecture.

Re: Antibody levels highly predictive of immune protection from symptomatic Covid

#33
post #27

Earlier quoted context omitted.

1. It was a single player, the rest were other staff 2. Vaccines don't prevent infection, they reduce severity by training the body's immune system. Natural exposure works the same way. This it is not surprising that 8/9 Yankees which tested positive were asymptomatic

This is incorrect - from population studies, we now know that both the mRNA vaccines reduce infection rates and reduce severity of symptoms for those who do get infected. In fact, they both show about 90% efficacy at preventing infection at all. That number is probably trending down a bit with all the new strains, but it is still very high.

I suppose that depends on how infection is defined. Nothing prevents the virus from entering the body and triggering a positive test result, especially when the tests are run with longer cycle times

Re: Antibody levels highly predictive of immune protection from symptomatic Covid

#35

I'm a little surprised this is in nature... Isn't that exactly what you'd expect?

The headline might be what you expect, but the article contains mathematical details about the relationship between antibody levels from the vaccines and neutralization. It also models antibody levels over time to see what immune protection we'll have in the future. Did we know the expected efficacy of the vaccine against severe Covid 750 days post-vaccine before?

Re: Antibody levels highly predictive of immune protection from symptomatic Covid

#36

Earlier quoted context omitted.

I believe the paper indicates otherwise, in regards to immunity. To help make sense of the paper, I read this Science Daily article that reviews it, and contains some comments from the paper's authors. https://www.sciencedaily.com/releases/2021/05/210517105727.h... Here, one of the people associated with the paper mentions: "Vaccination works very well to prevent both symptoms and severe disease in the short to mediu…

Does "6-fold lower level" mean "a sixth of the level"?

Yes

Re: Antibody levels highly predictive of immune protection from symptomatic Covid

#37
post #2

My father tested negative for spike specific antibodies 2 weeks after the 2nd Pfizer vaccine (he's not the only one), and as I didn't find any data on people who test negative (and I know that the vaccine has 94% efficiency preventing COVID), he's still mostly not leaving his apartment. He'll have a test against the viruses themselves next week, but he'll need to wait 2 weeks for the result for that test.

That doesn’t mean he doesn’t have protection. The antibody tests only look For one thing, but the body has many mechanisms of protection from the vaccine. That is one of the reasons why they’re not suggested to be used for the general population.

Re: Antibody levels highly predictive of immune protection from symptomatic Covid

#38

Earlier quoted context omitted.

Do you have a link to the research you’re citing from the other day? Also the basis for your implication that there’s a known difference in T cell response for natural immunity vs vaccine immunity?

Natural antibodies target several proteins: https://directorsblog.nih.gov/2021/05/18/human-antibodies-ta... Natural immunity robust and long lasting: https://www.nytimes.com/2020/11/17/health/coronavirus-immuni... Killer t cell importance: https://www.nature.com/articles/d41586-021-00367-7

Both the Pfizer and Moderna vaccines cause production of the full COVID spike protein. There is no reason to believe or even suspect that antibodies produced in response to that do not target the same regions of that spike protein that they would if produced in response to spike protein from the actual virus.

Re: Antibody levels highly predictive of immune protection from symptomatic Covid

#39

Earlier quoted context omitted.

If the vaccine is truly 95% effective in preventing infection, how did 9 fully vaccinated Yankees players all contract the virus?

I think most ball players got J&J, which has a decently lower prevention number. The encouraging news was that they all ended up asymptomatic, which is the next best thing

Yes, All of the Yankee players who were vaccinated had J&J. Also, most were completely asymptomatic and no one had serious symptoms. All-in-all, it was a success story for vaccines.

Re: Antibody levels highly predictive of immune protection from symptomatic Covid

#40
post #27

Earlier quoted context omitted.

1. It was a single player, the rest were other staff 2. Vaccines don't prevent infection, they reduce severity by training the body's immune system. Natural exposure works the same way. This it is not surprising that 8/9 Yankees which tested positive were asymptomatic

This is incorrect - from population studies, we now know that both the mRNA vaccines reduce infection rates and reduce severity of symptoms for those who do get infected. In fact, they both show about 90% efficacy at preventing infection at all. That number is probably trending down a bit with all the new strains, but it is still very high.

The Yankee players all had J&J vaccines, so not the mRNA variety.
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