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A T Cell Army against SARS-CoV-2

hellovirology.com

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Re: A T Cell Army against SARS-CoV-2

#11

Post by amluto »

vikramkr wrote: post #5
jonplackett wrote: post #2

I'm not a virologist or anything close, but reading this it seems like definitely good news? If I am understanding it right, it's saying many people already have T-cells from common colds that can to some extent recognise Covid-19, and those that have had Covid, even a mild case, have T-cells that seem to last quite a while.

This has been considered as a potential factor in explaining the variability in COVID outcomes for a while, both in the sense that prior infection with a cold virus could help protect from COVID through T cell responses and could make COVID worse through antibody responses. Cytotoxic T cell responses are definitely good, and it's also good to know that coronaviruses can induce these sorts of long term immunities (so…

I've also heard a hypothesis that infection with a common cold at the same time as COVID-19 could improve the outcome. The idea is that COVID-19 seems to suppress interferon production in infected cells but does not seem to suppress the response to interferon from outside the cells. So, if you have a normal cold, your lungs and/or airways might contain interferons, and those might help your innate immune system defend against COVID-19.

This hypothesis is entirely untested as far as I know.

Re: A T Cell Army against SARS-CoV-2

#12

Post by codeulike »

acqq wrote: post #9
dalore wrote: post #3

Earlier quoted context omitted.

Yes, this confirms what a few people have been trying to say, that we do have some form of prior immunity, it's not a novel virus in that everyone is 100% susceptible, and that anti body tests won't show up prevalence. In addition means we need a lower rate for herd immunity, if we haven't already got it in some places like New York and London. So the models of exponential growth was unfounded and it follows more a n…

> In addition means we need a lower rate for herd immunity No, it actually doesn't, the math functions differently than what is naively believed. See: https://statmodeling.stat.columbia.edu/2020/08/03/math-error... The R0 would have to be corrected to the higher value, which would mean that the herd immunity threshold for the susceptible part of population would have to be higher(!) Also, even among completely asympt…

That maths you link to literally says that the threshold for herd immunity among the entire population is indeed lowered. And that was the original posters point.

I think you're getting too caught up in the details. Its still good news, and it still means that herd immunity is easier and faster to achieve

Re: A T Cell Army against SARS-CoV-2

#13

Post by dalore »

acqq wrote: post #9
dalore wrote: post #3

Earlier quoted context omitted.

Yes, this confirms what a few people have been trying to say, that we do have some form of prior immunity, it's not a novel virus in that everyone is 100% susceptible, and that anti body tests won't show up prevalence. In addition means we need a lower rate for herd immunity, if we haven't already got it in some places like New York and London. So the models of exponential growth was unfounded and it follows more a n…

> In addition means we need a lower rate for herd immunity No, it actually doesn't, the math functions differently than what is naively believed. See: https://statmodeling.stat.columbia.edu/2020/08/03/math-error... The R0 would have to be corrected to the higher value, which would mean that the herd immunity threshold for the susceptible part of population would have to be higher(!) Also, even among completely asympt…

Your maths fails in real life. Seems to be only 10-20% of anti body prevalence is needed for herd immunity due to t-cell protection that wasn't taken into account. The Diamond Princess cruise ship, perfect floating petri dish for experiements, bore this out. Same with London and New York, reach the herd immunity levels of 10-20% and died out.

Try this maths https://judithcurry.com/2020/05/10/why-herd-immunity-to-covi...

Re: A T Cell Army against SARS-CoV-2

#14

Post by dalore »

tathougies wrote: post #8
dalore wrote: post #3

Earlier quoted context omitted.

Yes, this confirms what a few people have been trying to say, that we do have some form of prior immunity, it's not a novel virus in that everyone is 100% susceptible, and that anti body tests won't show up prevalence. In addition means we need a lower rate for herd immunity, if we haven't already got it in some places like New York and London. So the models of exponential growth was unfounded and it follows more a n…

> So the models of exponential growth was unfounded and it follows more a natural gompertz curve. The models of exponential growth were always unfounded. Exponential growth would have you believe that in a few short months, a sum larger than the entirety of the human population would get the virus. We knew then that it was ridiculous. The question wasn't if it was exponential or gompertz, but what the coefficients we…

At the start the only person trying to say it was a gompertz curve was Nobel Prize winner Professor Levitt. Everyone was using the Imperial College model which did say exponential growth and of which the governments around the world used to make policy. So to turn around and say now the models were unfounded is not useful as they were the models that were followed to make huge policy decisions. So it wasn't just people driving clicks, but governments making drastic changes to peoples lives based on these flawed models.

https://unherd.com/thepost/nobel-prize-winning-scientist-the...

Re: A T Cell Army against SARS-CoV-2

#16

Post by karmel »

js2 wrote: post #7
jonplackett wrote: post #2

I'm not a virologist or anything close, but reading this it seems like definitely good news? If I am understanding it right, it's saying many people already have T-cells from common colds that can to some extent recognise Covid-19, and those that have had Covid, even a mild case, have T-cells that seem to last quite a while.

From yesterday: > There are also preliminary hints that some people might have a degree of preexisting immunity against the new coronavirus. Four independent groups of scientists—based in the U.S., Germany, the Netherlands, and Singapore—have now found that 20 to 50 percent of people who were never exposed to SARS-CoV-2 nonetheless have significant numbers of T-cells that can recognize it. These “cross-reactive” cell…

Guilty as charged. And though I haven’t had a chance to read the Ed Yong article yet, I agree with the general stance that it’s surprising we understand anything at all about immunology, and what we do understand is incredibly surface level. As someone who has worked with both software/tech and science, I encourage you all to learn more about immunology— it’s a giant, multi-agent network that is incredibly complex, but the limitations of tooling mean we study it one parameter at a time, mostly using rudimentary classification frameworks (eg, cell types as determined by particular cell markers), rather than large data-driven approaches.

Re: A T Cell Army against SARS-CoV-2

#17

Post by graeme »

dalore wrote: post #3
jonplackett wrote: post #2

I'm not a virologist or anything close, but reading this it seems like definitely good news? If I am understanding it right, it's saying many people already have T-cells from common colds that can to some extent recognise Covid-19, and those that have had Covid, even a mild case, have T-cells that seem to last quite a while.

Yes, this confirms what a few people have been trying to say, that we do have some form of prior immunity, it's not a novel virus in that everyone is 100% susceptible, and that anti body tests won't show up prevalence. In addition means we need a lower rate for herd immunity, if we haven't already got it in some places like New York and London. So the models of exponential growth was unfounded and it follows more a n…

Not quite. Carl Bergstrom had a good thread on this. Basically, we saw a certain rate of growth. If this rate of growth happened despite half the population having T cell immunity, then it means the R0 must be higher than we thought, and therefore the herd immunity threshold in the susceptible population rises.

You do get a somewhat lower overall herd immunity threshold, but less than you thought.

https://twitter.com/CT_Bergstrom/status/1290744393796694016

Re: A T Cell Army against SARS-CoV-2

#18

Post by beagle3 »

dalore wrote: post #14
tathougies wrote: post #8

Earlier quoted context omitted.

> So the models of exponential growth was unfounded and it follows more a natural gompertz curve. The models of exponential growth were always unfounded. Exponential growth would have you believe that in a few short months, a sum larger than the entirety of the human population would get the virus. We knew then that it was ridiculous. The question wasn't if it was exponential or gompertz, but what the coefficients we…

At the start the only person trying to say it was a gompertz curve was Nobel Prize winner Professor Levitt. Everyone was using the Imperial College model which did say exponential growth and of which the governments around the world used to make policy. So to turn around and say now the models were unfounded is not useful as they were the models that were followed to make huge policy decisions. So it wasn't just peop…

There were quite a few others; it just happens that Michael Levitt is the highest profile person on that list, and essentially the only one to therefore be globally quoted;

But there are iirc ex surgeon-general equivalents in at least Germany and Israel and independents like Karl Deninger who had been saying essentially the same, with data to back themselves up, since March.

Re: A T Cell Army against SARS-CoV-2

#20

Post by ProcNetDev »

orblivion wrote: post #19

So is anybody floating the crazy idea of giving every reasonably healthy person a dose of the common cold as a poor man's vaccine?

Some people want to start giving out Oral Polio Vaccine (OPV) because it kicks the immune system into action. It is very safe, if you have already had a polio vaccine. I believe it has been shown that OPV reduced seasonal flu in areas where it was distributed.

https://science.sciencemag.org/content/368/6496/1187

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