14 ms·

> Herd immunity has been well-documented in the Brazilian city of Manaus, where researchers in the Lancet reported the prevalence of prior Covid-19 infection to

by danfo 6y ago

> Herd immunity has been well-documented in the Brazilian city of Manaus, where researchers in the Lancet reported the prevalence of prior Covid-19 infection to be 76%, resulting in a significant slowing of the infection. What, the linked study proves the opposite. A massive amount of death in Manaus in 2021, despite 'herd immunity' measured in October 2020. https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00183-5/fulltext https://www.thelancet.com/journals/lancet/article/PIIS0140-6... > Some medical experts privately agreed with my prediction that there may be very little Covid-19 by April but suggested that I not to talk publicly about herd immunity because people might become complacent and fail to take precautions or might decline the vaccine. But scientists shouldn’t try to manipulate the public by hiding the truth. Does he hear himself? You can't really liken wild guesses that lead to complacency/death as hiding the truth. It sounds like this guy should really stick to surgery.

timr 6y ago
> What, the linked study proves the opposite. A massive amount of death in Manaus in 2021, despite 'herd immunity' measured in October 2020. That is not a study. It is an editorial. It "proves" nothing, and instead advances a few alternative theories that might explain the discrepancy. However, it is not a complex situation. The following quote from the editorial is consistent with my personal belief after reading the original paper [1] that made the herd immunity claim: "The 76% estimate of past infection might have been biased upwards due to adjustments to the observed 52·5% (95% CI 47·6–57·5) seroprevalence in June, 2020, to account for antibody waning." This is true, but it understates the extent of the authors "adjustments". If you look at the original paper (Figure 2; linked below), they adjusted the raw data upward by a factor of about 3x. It is an...aggressive...modification to the raw data. The parsimonious explanation for what is being observed in Manaus is that the Science paper claiming herd immunity was wrong. The authors of this Lancet editorial go to great lengths to advance alternative explanations involving "variants", but these are all unfounded, convoluted alternatives. The simplest explanation is that the original paper was wrong. [1] https://science.sciencemag.org/content/371/6526/288 https://science.sciencemag.org/content/371/6526/288
- disgruntledphd2 6y ago
  I definitely found an epidemiologist on Twitter giving out about that study. The Science study used a convenience sample, which makes me believe that it's a very biased estimate of sero-prevalance.
  - timr 6y ago
    Yeah, there are possible issues with the way the Science paper collected their sample, as well. The authors of the Lancet editorial allude to this in the next sentence: "furthermore, comparisons of blood donors with census data showed no major difference in a range of demographic variables, and the mandatory exclusion of donors with symptoms of COVID-19 is expected to underestimate the true population exposure to the virus." Here, the Lancet writers are trying to argue that the sample wasn't that biased, and therefore the Science paper was right, and therefore the current infections are due to "variants". It's a very weird and convoluted argument. Comparison to demographic variables is irrelevant, and the second sentence doesn't address the actual concern with the Science paper (i.e. testing in Brazil was rare at the time of the study, so people with Covid sought out the study). Regardless, I think it's a red herring. It doesn't matter if the sample was biased or not -- you can look at the data as collected, and see that the upward adjustments were so aggressive that the conclusion of the Science paper is likely to be wrong.
- ttul 6y ago
  The latest episode of TWiV massacres the paper. It’s a good listen. https://www.microbe.tv/twiv/twiv-722/ https://www.microbe.tv/twiv/twiv-722/
marcodiego 6y ago
The only thing we can learn from Manaus is that waiting for herd immunity is a very bad idea.
- tinus_hn 6y ago
  Yeah, we better destroy the economy with lockdowns while waiting for vaccines that don’t work against these new strains, and then pay the price for herd immunity as well.
  - wavefunction 6y ago
    It seems the variants are arising in places where people have been mixing and not socially-distancing.
    - tinus_hn 6y ago
      Good luck telling these other governments to lock down to prevent that (assuming it prevents that, of course). That’s the difference between being an isolated nation and being on a continent. You can’t control what the other governments decide.
  - acdha 6y ago
    The economic damage is being done by the pandemic: people aren’t going to congregate when it’s risky and many businesses can’t survive without high in-person volume. Having lockdowns can get you back to the point where businesses can safely operate with community spread control measures (see e.g. Australia or Taiwan). What won’t work is attacking medical precautions or dissembling about vaccine effectiveness — and on that latter point, if you are really worried about variants the best way to stop them is carefully following medical advice to prevent community spread because each person who gets infected is something on the order of 10e9 chances for a new mutation which is more competitive. If people had worn masks and locked down a year ago this wouldn’t be anywhere near as bad a situation.
    - tinus_hn 6y ago
ttul 6y ago
It should be noted that WSJ’s opinion section is extremely politicized. Their regular news desk is separately edited and maintains decently high journalistic standards.
- burlesona 6y ago
  It's pretty weird actually. The news desk for the WSJ is among the best out there. Their news stories tend to be really dry in a good way - full of facts and figures, with very little in the way of click bait hyperbole. Their subscriber model is all about business people who want the details and not opinion... Which then makes the opinion desk at the WSJ a real oddball. It's consistently right-leaning, sometimes to the point of absurdity. I would think that a more varied field of opinion would resonate better with their target reader... but what do I know.
  - jrockway 6y ago
    Every time I accidentally stumble on the opinion section, I think to myself "today is the day I cancel my subscription." I'm hoping they Do Something about it. Just make it a separate $10/month add-on and see what the uptake is.
  - simplicio 6y ago
    The weirdest part is this leads to frequent items where the Op-Ed page makes factual claims that are directly contradicted by the news section in the same issue.
    - N1H1L 6y ago
      The recent opinion section, no less by the Editorial Board, at WSJ claimed that focusing on renewable energy sources led to the Texas power cuts [1]. While the paper, on the same day itself, reported the opposite [2]. Links: 1) https://www.wsj.com/articles/a-deep-green-freeze-11613411002#comments_sector https://www.wsj.com/articles/a-deep-green-freeze-11613411002... 2) https://www.wsj.com/articles/texas-freeze-power-grid-failure-electricity-market-incentives-11613777856 https://www.wsj.com/articles/texas-freeze-power-grid-failure...
rayiner 6y ago
> Does he hear himself? You can't really liken wild guesses that lead to complacency/death as hiding the truth. It sounds like this guy should really stick to surgery. It’s not a “wild guess.” There is data to support it. So what you’re really saying is that scientists should avoid discussing possible interpretations of the data for fear of what conclusions the public might draw. That’s not how science works and it isn’t a good way to build public trust in the process.

by danfo 6y ago

timr 6y ago

> What, the linked study proves the opposite. A massive amount of death in Manaus in 2021, despite 'herd immunity' measured in October 2020. That is not a study. It is an editorial. It "proves" nothing, and instead advances a few alternative theories that might explain the discrepancy. However, it is not a complex situation. The following quote from the editorial is consistent with my personal belief after reading the original paper [1] that made the herd immunity claim: "The 76% estimate of past infection might have been biased upwards due to adjustments to the observed 52·5% (95% CI 47·6–57·5) seroprevalence in June, 2020, to account for antibody waning." This is true, but it understates the extent of the authors "adjustments". If you look at the original paper (Figure 2; linked below), they adjusted the raw data upward by a factor of about 3x. It is an...aggressive...modification to the raw data. The parsimonious explanation for what is being observed in Manaus is that the Science paper claiming herd immunity was wrong. The authors of this Lancet editorial go to great lengths to advance alternative explanations involving "variants", but these are all unfounded, convoluted alternatives. The simplest explanation is that the original paper was wrong. [1] https://science.sciencemag.org/content/371/6526/288 https://science.sciencemag.org/content/371/6526/288

disgruntledphd2 6y ago
I definitely found an epidemiologist on Twitter giving out about that study. The Science study used a convenience sample, which makes me believe that it's a very biased estimate of sero-prevalance.
- timr 6y ago
  Yeah, there are possible issues with the way the Science paper collected their sample, as well. The authors of the Lancet editorial allude to this in the next sentence: "furthermore, comparisons of blood donors with census data showed no major difference in a range of demographic variables, and the mandatory exclusion of donors with symptoms of COVID-19 is expected to underestimate the true population exposure to the virus." Here, the Lancet writers are trying to argue that the sample wasn't that biased, and therefore the Science paper was right, and therefore the current infections are due to "variants". It's a very weird and convoluted argument. Comparison to demographic variables is irrelevant, and the second sentence doesn't address the actual concern with the Science paper (i.e. testing in Brazil was rare at the time of the study, so people with Covid sought out the study). Regardless, I think it's a red herring. It doesn't matter if the sample was biased or not -- you can look at the data as collected, and see that the upward adjustments were so aggressive that the conclusion of the Science paper is likely to be wrong.
ttul 6y ago
The latest episode of TWiV massacres the paper. It’s a good listen. https://www.microbe.tv/twiv/twiv-722/ https://www.microbe.tv/twiv/twiv-722/

marcodiego 6y ago

The only thing we can learn from Manaus is that waiting for herd immunity is a very bad idea.

tinus_hn 6y ago
Yeah, we better destroy the economy with lockdowns while waiting for vaccines that don’t work against these new strains, and then pay the price for herd immunity as well.
- wavefunction 6y ago
  It seems the variants are arising in places where people have been mixing and not socially-distancing.
  - tinus_hn 6y ago
    Good luck telling these other governments to lock down to prevent that (assuming it prevents that, of course). That’s the difference between being an isolated nation and being on a continent. You can’t control what the other governments decide.
- acdha 6y ago
  The economic damage is being done by the pandemic: people aren’t going to congregate when it’s risky and many businesses can’t survive without high in-person volume. Having lockdowns can get you back to the point where businesses can safely operate with community spread control measures (see e.g. Australia or Taiwan). What won’t work is attacking medical precautions or dissembling about vaccine effectiveness — and on that latter point, if you are really worried about variants the best way to stop them is carefully following medical advice to prevent community spread because each person who gets infected is something on the order of 10e9 chances for a new mutation which is more competitive. If people had worn masks and locked down a year ago this wouldn’t be anywhere near as bad a situation.
  - tinus_hn 6y ago

ttul 6y ago

It should be noted that WSJ’s opinion section is extremely politicized. Their regular news desk is separately edited and maintains decently high journalistic standards.

burlesona 6y ago
It's pretty weird actually. The news desk for the WSJ is among the best out there. Their news stories tend to be really dry in a good way - full of facts and figures, with very little in the way of click bait hyperbole. Their subscriber model is all about business people who want the details and not opinion... Which then makes the opinion desk at the WSJ a real oddball. It's consistently right-leaning, sometimes to the point of absurdity. I would think that a more varied field of opinion would resonate better with their target reader... but what do I know.
- jrockway 6y ago
  Every time I accidentally stumble on the opinion section, I think to myself "today is the day I cancel my subscription." I'm hoping they Do Something about it. Just make it a separate $10/month add-on and see what the uptake is.
- simplicio 6y ago
  The weirdest part is this leads to frequent items where the Op-Ed page makes factual claims that are directly contradicted by the news section in the same issue.
  - N1H1L 6y ago
    The recent opinion section, no less by the Editorial Board, at WSJ claimed that focusing on renewable energy sources led to the Texas power cuts [1]. While the paper, on the same day itself, reported the opposite [2]. Links: 1) https://www.wsj.com/articles/a-deep-green-freeze-11613411002#comments_sector https://www.wsj.com/articles/a-deep-green-freeze-11613411002... 2) https://www.wsj.com/articles/texas-freeze-power-grid-failure-electricity-market-incentives-11613777856 https://www.wsj.com/articles/texas-freeze-power-grid-failure...

rayiner 6y ago

> Does he hear himself? You can't really liken wild guesses that lead to complacency/death as hiding the truth. It sounds like this guy should really stick to surgery. It’s not a “wild guess.” There is data to support it. So what you’re really saying is that scientists should avoid discussing possible interpretations of the data for fear of what conclusions the public might draw. That’s not how science works and it isn’t a good way to build public trust in the process.