144 Comments

Chris is 100% wrong. Everything in Thomas Pueyos article is exact and correct,clear and focused. I have called each of the 3 world waves when there was only a few 100 cases.

[In 1st wave, (WILD Strain), thats 100 cases OUTSIDE China. ])

I know he is right.

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Thank you for your confidence! I can also be wrong though. So it's always important to check each other out. But disagreement must be constructive though.

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Jul 13, 2021Liked by Tomas Pueyo

Another great article Tomas. I think one point is too simplistic; 'Delta will tear through those unvaccinated, but that’s their prerogative'. There are many people that cannot have a vaccine even if they wanted to (eg immunosuppressed, etc), so they basically have to continue hiding away in isolation while the virus rips through society.

As you indeed said, 'If your location values the freedom of its people to make the wrong decisions (as long as they don’t impact others)...' - it DOES impact others. It is certainly unfortunate if you live somewhere the govt and/or populace is making that wrong/foolish decision for you against your will, but that's a separate argument...

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Yes. This is another very hard problem to properly analyze. Given the conversation about this, I am tempted to tackle it next.

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Jul 26, 2021Liked by Tomas Pueyo

And if hospitals are overrun with covid patients then staff are overworked and care will suffer, and anyway care for all other types of health issues will also suffer due to lack of infrastructure and health care workers

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Jul 13, 2021Liked by Tomas Pueyo

There are some promising discussions on fractionation to rapidly increase vaccine supply: https://twitter.com/bencowling88/status/1412202994192420868.

Summary: just as the recommended dosing schedule is whatever was used in the trials and not necessarily the optimal timing, so is the quantity of vaccine given.

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author

AGREED!

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Jul 13, 2021Liked by Tomas Pueyo

How should parents of kids under 12 think about Delta? Everyone in their family is fully vaccinated, but the general public is not.

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I haven't read the data on vaccines for young children. FWIW, I will vaccinate mine when I can.

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Jul 13, 2021Liked by Tomas Pueyo

I would have liked to see mention of this in your "takeaways" — today we don't know if children and the immunosuppressed will be eligible for safe vaccines within months, this year, or even next year. This lack of transparency is one of the fuels behind anti-science attitudes.

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I know. You're right. It's just a massive undertaking to go deep enough on the current evidence to make up an independent opinion.

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Jul 13, 2021Liked by Tomas Pueyo

clarification: I wasn't criticizing you for overlooking that in your article; I'm upset with the medical community's silence on the topic.

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Jul 13, 2021Liked by Tomas Pueyo

Good question, and more specifically,

- are children more likely to get infected, or infect others with the delta variant than with previous variants?

- are children more at risk of hospitalization, death or long covid with delta?

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Jul 13, 2021Liked by Tomas Pueyo

I believe you should protect them as much as possible until they can be vaccinated. Look at the summer camp fiascos that have happened already.

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Jul 24, 2021Liked by Tomas Pueyo

Hi Tomas, hope your doing fine. We have translated this post into Portuguese, here: https://altruismoeficaz.com.br/2021/07/24/variante-delta-tudo-o-que-precisa-de-saber/

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Jul 18, 2021Liked by Tomas Pueyo

In your example, the herd immunity threshold would be (1-1/8)=87.5%, which with a vaccine efficicacy against transmission of 90% would require 87.5/90%=97% of the population to be vaccinated. That vaccine efficacy against transmission is probably a bit on the optimistic side. More likely it is around 85%.

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Jul 15, 2021Liked by Tomas Pueyo

Please add year to article date under your namr. I fear you have a task for a long time yet.

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Jul 14, 2021Liked by Tomas Pueyo

"An R0 of 8 is bad news for herd immunity. It puts its threshold at ~90% of people protected, which is impossible to reach if vaccines are only 65% protective of infection. Booster shots are necessary." If we get 90%+ of people vaccinated, where's the problem if people catch the disease but don't get very sick? The most important thing should remain to prevent as much as possible Long COVID, hospitalizations and deaths, things for which the current vaccines seem very effective. Yes, the virus will probably continue to mutate and it might be necessary down the road to get vaccinated again, much like with other respiratory viruses, but we could really get back our lives in the meantime and going forward. I don't think it will ever be possible to prevent all deaths or any complications associated with COVID for some people - after all, we never achieved this with the flu, even 100 years after the Spanish Flu pandemic. Life is not without risks, we have to accept that. The end of a pandemic does not equate that no one dies from the disease anymore. P.S.: There were many immunocompromised people in the Israeli study that you mention, it was not a population study and there are still other studies from Israel that mention 90 to 95% efficacy against a COVID infection from our current vaccines.

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Wholeheartedly agreed. I say so in the article.

The point I wanted to highlight with that is that you really need to push for full vaccination, because at this point most ppl will likely get infected. They better have the vaccine protection when they do.

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Jul 13, 2021Liked by Tomas Pueyo

Great article. Again. The world misses these articles of yours. And it's not over yet, though closer.

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If you asked me 1.5 years ago I def didn't think I'd be writing these now...

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Aug 16, 2021Liked by Tomas Pueyo

After reading this I worked up a dashboard to show what happens to deaths as values such as proportion vaccinated, vaccine efficacy, R0 etc are varied. Available here:

https://davepid.shinyapps.io/new2/

Regards

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This is cool, thx!

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Aug 8, 2021Liked by Tomas Pueyo

Great article Tomas. My concerns are now around the division opening up in Australia and world wide with vaccinated vs unvaccinated. I just hope everyone stays united and our society does not crumble. Here is a link to a YouTube slideshow that keeps everything in perspective.

https://youtu.be/b8HUSboCsjw

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author

Thx!

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Jul 26, 2021Liked by Tomas Pueyo

The article is accurate til it gets the the herd immunity section.

The people who have recovered from covid also figure into herd immunity. So it should be calculated as vaccinated + recovered. Not vaccinated alone. This is much higher number.

Another way to estimate immunity is via antibodies. People have antibodies during & for a few months after an infection. And also anytime that same infection is circulating in the general population. In other words, whenever the body is exposed, antibodies are produced. In the UK the estimates are 80-90% population. So they should be close to herd immunity.

Then the question is whether infection produces long term immunity. Research suggests yes. Nature had to 2 studies relative to this. In the first, most people who removed from SARS-CoV1 still had immune response 17 years later (via bone marrow testing.) Second study, for SARS-CoV2 (covid 19) antibodies fade but b/t cell immunity looks to “likely lifetime” their words. And also, NIH has an opinion piece suggesting lifetime immunity. And also partial cross immunity between corona viruses.

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Nice post Tomas.

Good news today : if you have had 2 doses of the Pfizer (and likely Moderna), or 2 doses of Astra-Zeneca/Covishield, effectiveness against the delta variant is great and mostly comparable to the alpha variant. Here's the link to the study : https://www.nejm.org/doi/full/10.1056/NEJMoa2108891

Jean-Philippe Boucher

Hospital pharmacist, Drummondville, Quebec, Canada

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Jul 19, 2021Liked by Tomas Pueyo

Am I allowed to ask why prevention and early treatment aren't part of the equation, Tomas? I've been a fan since the early days, but why isn't it part of your equation? The WHO, at who.int - link below - reports the World Health Organization's own current analysis finds that there’s a 95% chance that a repurposed drug causes AT LEAST a 64% reduction in mortality based on THEIR analysis of the data from 1419 patients in the seven randomized controlled trials they chose as the best ones to consider. You know CI 95% means 95% confidence interval... The latest info from the WHO - per their Therapeutics "living guideline”. The Who estimate for the reduction in mortality is 17% higher than the lower end of the CI that I noted.

As of 6 July 2021. Version 5. Search the PDF at https://apps.who.int/iris/rest/bitstreams/1354702/retrieve for “0.19” to see the source.

Search the PDF at https://apps.who.int/iris/rest/bitstreams/1354702/retrieve for “0.19” to see the source. Other meta-analyses by the BiRD, etc., etc. also find great efficacy. Especially when used for prevention, and if we combine the risk reduction if it's used for prevention and then if necessary treatment... WOW!

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Ok let me look into it. Thx for asking

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Jul 18, 2021Liked by Tomas Pueyo

Excellent. Just an idea: could it make sense to combine the current vaccination effort with a simple lottery? Per example celebrating every 1% vaccination rate gain by handing out 5.000$ to 10 numbers in the vaccinated pool of people. With a single 500.000$ super-prize among all vaccinated once 90% has been reached? I think we have to become much more creative to get numbers up and defeat the virus. The prizes may be discussed but the addition of the lottery system could potentially create a network effect.

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Tried in Ohio, didn't work much...

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Jul 18, 2021Liked by Tomas Pueyo

>If we assume an R0 of 8 and a vaccine effectiveness of 90% against transmission, you need at least 90% of the population vaccinated before you can declare victory. No country is getting close to that.

We're currently at 86% of the adult population here in Malta having received at least one dose, so I would have to disagree with that. Daily cases were in the single digits before an outbreak mostly among unvaccinated tourists brought it back to triple digits.

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You're precisely right! Small countries are edge cases. Glad Malta is one of them.

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