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Spread of Delta variant driven by both immune escape and increased infectivity

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Re: Spread of Delta variant driven by both immune escape and increased infectivity

#61

Post by alex_c »

TheBlight wrote: post #2

I was told this is a pandemic of the unvaccinated.

OK, I'll bite.

Ontario had 554 new reported cases of COVID yesterday. Of these cases:

- 319 were not vaccinated (213 of these were 12+ and therefore eligible to be vaccinated)

- 56 were partially vaccinated

- 136 were fully vaccinated

- 44 unknown

In other words, roughly 16% of the population (eligible but not vaccinated) is driving close to 40% of reported cases.

OK, but reported cases are blah blah, who cares, right? Individual cases will vary in severity and everyone can make their own decisions about risk tolerance, etc etc. But the strain on our health care system is the biggest cost we all share in the pandemic regardless of personal choices, so let's look at ICU numbers instead:

- 113 unvaccinated

- 7 partially vaccinated

- 8 fully vaccinated

You can draw your own conclusions.

Source: https://www.reddit.com/r/ontario/comments/pkbgrz/ontario_sep...

Re: Spread of Delta variant driven by both immune escape and increased infectivity

#62

Post by alecst »

zamfi wrote: post #9
spuz wrote: post #3

> it takes eight times as many antibodies from a vaccinated individual to block the virus If this is the case, then how can we explain how vaccinated individuals experience less severe symptoms and fewer deaths? Is it because once vaccinated, the immune system is able to respond to this 8x higher demand?

Every article that leads with this kind of stat is guilty of lying by omission. The typical immune response produces 10,000-100,000 times more antibodies than “necessary” to fight an infection. If delta needs 8x more antibodies, then, well, our immune response is only overkill by a factor of 1,250-12,500. Perhaps that’s enough for some of the virus to escape. But it’s still plenty to prevent severe illness! Of course…

I'm open minded to what you're saying but help me understand how both this

> The typical immune response produces 10,000-100,000 times more antibodies than “necessary” to fight an infection.

can be true, and how vaccines are basically 90% effective at preventing symptomatic illness (kinda sorta, leaning towards the high end.)

Feels like the numbers don't match up.

Re: Spread of Delta variant driven by both immune escape and increased infectivity

#64

Post by jfrankamp »

TheBlight wrote: post #2

I was told this is a pandemic of the unvaccinated.

You were told correctly?

Brad Little of Idaho says greater than 98% of cases, hospitalizations and deaths are unvaccinated (link below).

Cases are probably the most unstable of those stats, but the point is unvaccinated folks are bearing the majority of the pain.

https://twitter.com/GovernorLittle/status/142593002008663654...

Re: Spread of Delta variant driven by both immune escape and increased infectivity

#65

Post by qzw »

rajin444 wrote: post #47
qzw wrote: post #33

Earlier quoted context omitted.

That's kind of beside the point. With natural infection, the risk of severe illness is also much higher. So for most people trying to get "better" immunity by natural infection is not a good tradeoff. It's kind of like saying that since it's extremely rare to get bitten by a shark twice, you should try to get a shark to bite you once in order to acquire "immunity" to sharks.

A lot of vaccine hesitancy (in the US at least) is driven by refusal to acknowledge natural immunity. Ignoring it is another "noblie lie" to help drive up vaccine numbers. It's much easier to say "just get the vaccine". However, it's a massive ethical violation if the vaccine provides no improvement over natural immunity. It's still pretty bad if it only provides minimal improvement. "Just get the vaccine" would be a…

I think far more vaccine hesitancy in the US is driven by glorifying "natural immunity", especially when it's not clearly stated whether it's pre- or post-COVID immunity that's being touted. For example, I can't tell from your comment whether your position is that people shouldn't get vaccinated at all or whether they shouldn't do so if they've already had COVID. The latter position is debatable, but the former would be firmly contrary to pretty much all known scientific evidence (as long as we're talking about the general population and not a specific subgroup).

Re: Spread of Delta variant driven by both immune escape and increased infectivity

#66

Post by achenatx »

rajin444 wrote: post #47
qzw wrote: post #33

Earlier quoted context omitted.

That's kind of beside the point. With natural infection, the risk of severe illness is also much higher. So for most people trying to get "better" immunity by natural infection is not a good tradeoff. It's kind of like saying that since it's extremely rare to get bitten by a shark twice, you should try to get a shark to bite you once in order to acquire "immunity" to sharks.

A lot of vaccine hesitancy (in the US at least) is driven by refusal to acknowledge natural immunity. Ignoring it is another "noblie lie" to help drive up vaccine numbers. It's much easier to say "just get the vaccine". However, it's a massive ethical violation if the vaccine provides no improvement over natural immunity. It's still pretty bad if it only provides minimal improvement. "Just get the vaccine" would be a…

Ive suspected all along the massive media push that "natural infection only generates immunity for 90 days" or "6 months" or whatever would turn out to be false. The media played up anecdotes of reinfections but there was never any actual data.

The thing is they never lied. At the time they made those statements the virus had only been studied for that long.

By the time the vaccines were created the "reinfection" idea was entrenched (even though not proven) and the vaccine was recommended just in case.

Re: Spread of Delta variant driven by both immune escape and increased infectivity

#67

Post by nanis »

achenatx wrote: post #35
clipradiowallet wrote: post #28

Earlier quoted context omitted.

> Dumb people are going to want to go to covid parties When I was a child, parents would inform other parents when a child had chickenpox; so they could have a sleepover. That was normal practice in the portion of the USA I grew up in. As a result, nearly everyone my age has natural immunity to chickenpox. I share that anecdote to point out that the idea of an "infection party" is a really old idea that was practiced…

chickenpox has a death rate of .001% Covid has a death rate of .5% (higher for older people, lower for younger) flu has a death rate of .1% and you dont see people having flu parties..

> Covid has a death rate of .5% (higher for older people, lower for younger)

That is a very bold statement, given that mild cases are less likely to be recorded in official data sets, affecting the denominator much more for younger people than older people.

What we do know is that a total of 412 people between the ages 0-17 are known to have died from Covid19 in the U.S. since January 1, 2020. Total deaths from all causes in that age group was 55,352 for the same period and the total number of Covid19 deaths in the U.S. for the same period was 643,858. Out of that 502,863 were among those older than 65 years of age.

If we take your claimed death rate of 0.5% at face value, 412 deaths implies 82,400 infections. According to the U.S. Census Bureau[2], there are about 74 million people under the age of 18 in the U.S.

So, the assumption of 0.5% IFR implies that only 0.11% of those under the age of 18 got infected with Covid19 in the same time period.

Therefore, either the 0.5% IFR overestimates the actual IFR by about 500-600%, or Covid19 is just not that infectious among those younger than 18.

I am going to with the assumption that 0.5% IFR is way too high. In that case, it makes absolute sense not to disrupt the lives of young children to the extent we have already disrupted and allow them to gain natural immunity through each wave.

[1]: https://data.cdc.gov/NCHS/Provisional-COVID-19-Deaths-by-Sex...

[2]: https://www.census.gov/quickfacts/fact/table/US/PST045219

Re: Spread of Delta variant driven by both immune escape and increased infectivity

#68

Post by cloakandswagger »

achenatx wrote: post #60
cloakandswagger wrote: post #45

Earlier quoted context omitted.

> Public health messages need to be kept simple. By simple you mean, dishonest? People aren't as dumb as our betters believe. They pick up on obvious lies ("stop buying masks" => "everyone must wear a mask"), dishonesty ("ivermectin is for animals") and inconsistencies that fly in the face of intuition ("even if you had covid you still need the vaccination"). If the powers that be would stop trying to "shape human be…

I agree that the public health messaging has quite a number of statements that may not be true. But they may not be false either. Instead of lies, scientists are erring on the side of caution for what they do know. I agree that sanctimonious public health and politicians have created a lot of distrust. Their messaging is condescending, manipulative, and generates the direct opposite of what they are trying to achieve…

There can be honesty even if they are playing it safe: Just state plainly that the data is inconclusive, things are moving quickly and this is the best estimation they currently have. Spewing out patronizing misinformation (see the FDA's sassy "You are not a horse" tweet) is counter-productive.

Re: Spread of Delta variant driven by both immune escape and increased infectivity

#69

Post by achenatx »

cartoonworld wrote: post #49
achenatx wrote: post #30

Earlier quoted context omitted.

The assertion is not correct, viruses do not need to spread to new hosts to experience meaningful mutation.

Yes, it is much more precise to state that they must be replicating in order to mutate. I've edited my comment to reflect this, Thanks :) If RNA is damaged and changed and the virus particle is destroyed or for some reason never replicates, I don't count that as mutating, but then again what do I know.

bacteria mostly need to be replicating to spread mutations as well.

There are mechanisms for bacteria to uptake dna in the environment and incorporate it (e.g. antibiotic resistance). But without replication of the bacteria the resistance wont spread.

One interesting point is that in general biology they teach that lamarckian evolution doesnt exist, but bacterial uptake of DNA demonstrates that it does exist.

Re: Spread of Delta variant driven by both immune escape and increased infectivity

#70

Post by qzw »

alecst wrote: post #62
zamfi wrote: post #9

Earlier quoted context omitted.

Every article that leads with this kind of stat is guilty of lying by omission. The typical immune response produces 10,000-100,000 times more antibodies than “necessary” to fight an infection. If delta needs 8x more antibodies, then, well, our immune response is only overkill by a factor of 1,250-12,500. Perhaps that’s enough for some of the virus to escape. But it’s still plenty to prevent severe illness! Of course…

I'm open minded to what you're saying but help me understand how both this > The typical immune response produces 10,000-100,000 times more antibodies than “necessary” to fight an infection. can be true, and how vaccines are basically 90% effective at preventing symptomatic illness (kinda sorta, leaning towards the high end.) Feels like the numbers don't match up.

Both can be true if ~10% of the population do not have a "typical immune response" to the vaccine. This can be due to a number of factors such as age, preexisting conditions, general health, etc. Plus the immunity from vaccination "wears off" over time, and some of the earliest recipients are now 8+ months post vaccination.
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