5 ms·

> The only way to judge the effectiveness of measures is to see how many people have actually been infected Can anyone provide links to recent peer-reviewed pr

> The only way to judge the effectiveness of measures is to see how many people have actually been infected Can anyone provide links to recent peer-reviewed primary sources that estimate the number of individuals who have been infected in the U.S.? If ~70% of people are asymptomatic, and we assume just about everyone has been exposed to and infected by the virus - haven't we already achieved herd immunity in the U.S.? EDIT: Answered in solid source provided by animats - the seroprevalance estimate for the U.S. is 21.6% (95% CI - 21.2% to 22.22%). I also found a couple recent primary sources regarding the asymptomatic rate, see thread below.

bagels 5y ago
This assumes infection leads to immunity. It doesn't seem to be clear that this is true.
- jampekka 5y ago
  It's the default assumption given practically every other known virus, and is the core assumption of all epidemiological modeling. Somehow all what is known from epidemiology and virology has been thrown out of the window during COVID. If SARS-CoV-2 is somehow involved the sky is falling on us on any moment unless otherwise proven. Bizarre. Don't know if they have a part in this, but at least it's extremely profitable for pharma to assume there's no immunity but what they provide.
- criticaltinker 5y ago
  Here are some primary sources which support the fact that infection leads to robust and durable immunity. [1] SARS-CoV-2 infection induces long-lived bone marrow plasma cells in humans https://www.nature.com/articles/s41586-021-03647-4.pdf https://www.nature.com/articles/s41586-021-03647-4.pdf [2] Necessity of COVID-19 vaccination in previously infected individuals https://www.medrxiv.org/content/10.1101/2021.06.01.21258176v3.full.pdf https://www.medrxiv.org/content/10.1101/2021.06.01.21258176v...
  - galangalalgol 5y ago
    I know three people who got it twice and another who is a friend of a friend. Only one of those is known to be immunocompromised. Two of those got it the second time after also being vaccinated. I do wonder though if some of the second cases aren't people going in with the flu and having some covid fragments in their nose.
    - xienze 5y ago
      > I do wonder though if some of the second cases aren't people going in with the flu and having some covid fragments in their nose. This is why using PCR tests cranked up to absurd cycle counts isn't the best way to determine _infection_.
      - galangalalgol 5y ago
        though nations like Australia that did flu checks last year estimated it was almost absent, and of those that tested positive very small percentages were vaccinated, so if its the flu, the covid vaccine is the best flu vaccine ever.
  - azinman2 5y ago
    N=1, but I now know many people who have been vaccinated that have since been infected, where as up until recently I knew 2 people who got it this entire time (I'm in SF). One of these new people is a co-worker who got covid last year, then got Pfizer vaccinated, then got it again and almost was hospitalized. He's 29 and fit, and as far as I know, is not immunocompromised. All the data shows that vaccination provides protection, but with all these new variants coming out (expect more over time), I don't believe herd immunity is any more possible than herd immunity with the flu or common cold.
    - jMyles 5y ago
      > I don't believe herd immunity is any more possible than herd immunity with the flu or common cold. This seems to me to be a very strange thing to say. We know precisely what the pattern is for herd immunity in the case of a coronavirus, because four of them cause what you are calling a "common cold". It's endemic equilibrium. To my knowledge, there is no dispute among experts on this point. So to say that we can't achieve herd immunity because of its similarity to a virus against which we are indeed herd immune is, at best, begging the question. If you have six minutes, this is a very acute description of the endemic equilibrium effect of herd immunity: https://www.youtube.com/watch?v=RsmDJYhteQs https://www.youtube.com/watch?v=RsmDJYhteQs
IfOnlyYouKnew 5y ago
The fact that more people are in the hospital in Florida right now than at any time in the last two years would seem to disprove any speculation of here immunity.
- kevin_thibedeau 5y ago
  How many have been infected twice?
- jMyles 5y ago
  Can we stop with this please? > The fact that more people are in the hospital in Florida right now than at any time in the last two years THIS IS NOT TRUE. The metric you are describing is hospital census, which is _not_ at an all-time high right now. What is at an all time high? The percentage of people in the hospital who have tested positive for SARS-CoV-2, regardless of their presentation. The roundtable just yesterday confirmed that there are hospitals which have near 100% positivity, despite 80% presenting for things unrelated to a respiratory infection. Some people are there for blunt trauma or routine surgery, but have tested positive for SARS-CoV-2. I just don't understand the point of constantly misrepresenting this metric. It muddies the waters of actual concerns about the spread of the virus by making it seem like those are are concerned are dishonest. Stop it.
  - aix1 5y ago
    I think the media is at least partly to blame for this. I have the greatest respect for the BBC, but look at this headline: Covid third wave: Florida surpasses all-time record for hospital admissions. Totally unsupported by the article. https://www.bbc.co.uk/news/world-us-canada-58077209 https://www.bbc.co.uk/news/world-us-canada-58077209 With regards to metrics that are peaking, FT reports that "Occupancy in the south-eastern US state’s intensive care units is on course to hit an all-time high by this weekend." (But then again, I've no idea whether this is actually accurate since they don't cite their source. Besides, it's clearly an extrapolation.) https://www.ft.com/content/21ed4e9c-2b20-4a9d-bf38-6b76212beef8 https://www.ft.com/content/21ed4e9c-2b20-4a9d-bf38-6b76212be...
comicjk 5y ago
If we assume everyone has been infected? Why would we assume that? The estimates I've seen (including asymptomatic) are around 1/3 infected. The source you cited is from 2020, so it doesn't tell us much about today.
- criticaltinker 5y ago
  Yup good catch about the old source, I removed that from my comment. The source provided by animats puts the seroprevalence at 21.6% for the U.S. I think that should be a lower bound of the number of individuals who have been infected, given antibody levels wane over time (even though immunity does not necessarily wane).
nradov 5y ago
The CDC estimates that 36% of Americans have been infected. Of those, only 15% were completely asymptomatic but most had mild symptoms. https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/burden.html https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/burd...
- criticaltinker 5y ago
  Thanks for pointing that out and doing the math. I did some digging, here is the paper outlining the methods and data sources for the numbers on the page you linked to [1]. That paper cites two other papers used to estimate the asymptomatic proportion [2][3]. Here is a more recent systematic review [4], which estimates that at least 33% of infections are asymptomatic. And another recent paper which estimates the lower bound for asymptomatic proportion (AP) to be 37%, with an upper bound of 67% [5]. "The estimated AP varied with age, from 74% (95% CI 65–90%) for < 20 years, to 61% (95% CI 57–65%) for the 50–59 years age-group." [5] [1] Estimated Incidence of Coronavirus Disease 2019 (COVID-19) Illness and Hospitalization—United States, February–September 2020 https://academic.oup.com/cid/article/72/12/e1010/6000389 https://academic.oup.com/cid/article/72/12/e1010/6000389 [2] Estimating the extent of asymptomatic COVID-19 and its potential for community transmission: Systematic review and meta-analysis https://jammi.utpjournals.press/doi/pdf/10.3138/jammi-2020-0030 https://jammi.utpjournals.press/doi/pdf/10.3138/jammi-2020-0... [3] Age-dependent effects in the transmission and control of COVID-19 epidemics https://www.nature.com/articles/s41591-020-0962-9 https://www.nature.com/articles/s41591-020-0962-9 [4] The Proportion of SARS-CoV-2 Infections That Are Asymptomatic https://www.acpjournals.org/doi/full/10.7326/M20-6976 https://www.acpjournals.org/doi/full/10.7326/M20-6976 [5] Estimating the asymptomatic proportion of SARS-CoV-2 infection in the general population: Analysis of nationwide serosurvey data in the Netherlands https://link.springer.com/article/10.1007/s10654-021-00768-y https://link.springer.com/article/10.1007/s10654-021-00768-y
  - nradov 5y ago
    Asymptomatic is kind of a fuzzy concept so the numbers will vary based on methodology. If you test positive and then have a bit of diarrhea one day is that a COVID-19 symptom or the consequences of a bad burrito? In mild cases there's no way to be sure. https://www.cdc.gov/coronavirus/2019-ncov/symptoms-testing/symptoms.html https://www.cdc.gov/coronavirus/2019-ncov/symptoms-testing/s...

bagels 5y ago

This assumes infection leads to immunity. It doesn't seem to be clear that this is true.

jampekka 5y ago
It's the default assumption given practically every other known virus, and is the core assumption of all epidemiological modeling. Somehow all what is known from epidemiology and virology has been thrown out of the window during COVID. If SARS-CoV-2 is somehow involved the sky is falling on us on any moment unless otherwise proven. Bizarre. Don't know if they have a part in this, but at least it's extremely profitable for pharma to assume there's no immunity but what they provide.
criticaltinker 5y ago
Here are some primary sources which support the fact that infection leads to robust and durable immunity. [1] SARS-CoV-2 infection induces long-lived bone marrow plasma cells in humans https://www.nature.com/articles/s41586-021-03647-4.pdf https://www.nature.com/articles/s41586-021-03647-4.pdf [2] Necessity of COVID-19 vaccination in previously infected individuals https://www.medrxiv.org/content/10.1101/2021.06.01.21258176v3.full.pdf https://www.medrxiv.org/content/10.1101/2021.06.01.21258176v...
- galangalalgol 5y ago
  I know three people who got it twice and another who is a friend of a friend. Only one of those is known to be immunocompromised. Two of those got it the second time after also being vaccinated. I do wonder though if some of the second cases aren't people going in with the flu and having some covid fragments in their nose.
  - xienze 5y ago
    > I do wonder though if some of the second cases aren't people going in with the flu and having some covid fragments in their nose. This is why using PCR tests cranked up to absurd cycle counts isn't the best way to determine _infection_.
    - galangalalgol 5y ago
      though nations like Australia that did flu checks last year estimated it was almost absent, and of those that tested positive very small percentages were vaccinated, so if its the flu, the covid vaccine is the best flu vaccine ever.
- azinman2 5y ago
  N=1, but I now know many people who have been vaccinated that have since been infected, where as up until recently I knew 2 people who got it this entire time (I'm in SF). One of these new people is a co-worker who got covid last year, then got Pfizer vaccinated, then got it again and almost was hospitalized. He's 29 and fit, and as far as I know, is not immunocompromised. All the data shows that vaccination provides protection, but with all these new variants coming out (expect more over time), I don't believe herd immunity is any more possible than herd immunity with the flu or common cold.
  - jMyles 5y ago
    > I don't believe herd immunity is any more possible than herd immunity with the flu or common cold. This seems to me to be a very strange thing to say. We know precisely what the pattern is for herd immunity in the case of a coronavirus, because four of them cause what you are calling a "common cold". It's endemic equilibrium. To my knowledge, there is no dispute among experts on this point. So to say that we can't achieve herd immunity because of its similarity to a virus against which we are indeed herd immune is, at best, begging the question. If you have six minutes, this is a very acute description of the endemic equilibrium effect of herd immunity: https://www.youtube.com/watch?v=RsmDJYhteQs https://www.youtube.com/watch?v=RsmDJYhteQs

IfOnlyYouKnew 5y ago

The fact that more people are in the hospital in Florida right now than at any time in the last two years would seem to disprove any speculation of here immunity.

kevin_thibedeau 5y ago
How many have been infected twice?
jMyles 5y ago
Can we stop with this please? > The fact that more people are in the hospital in Florida right now than at any time in the last two years THIS IS NOT TRUE. The metric you are describing is hospital census, which is _not_ at an all-time high right now. What is at an all time high? The percentage of people in the hospital who have tested positive for SARS-CoV-2, regardless of their presentation. The roundtable just yesterday confirmed that there are hospitals which have near 100% positivity, despite 80% presenting for things unrelated to a respiratory infection. Some people are there for blunt trauma or routine surgery, but have tested positive for SARS-CoV-2. I just don't understand the point of constantly misrepresenting this metric. It muddies the waters of actual concerns about the spread of the virus by making it seem like those are are concerned are dishonest. Stop it.
- aix1 5y ago
  I think the media is at least partly to blame for this. I have the greatest respect for the BBC, but look at this headline: Covid third wave: Florida surpasses all-time record for hospital admissions. Totally unsupported by the article. https://www.bbc.co.uk/news/world-us-canada-58077209 https://www.bbc.co.uk/news/world-us-canada-58077209 With regards to metrics that are peaking, FT reports that "Occupancy in the south-eastern US state’s intensive care units is on course to hit an all-time high by this weekend." (But then again, I've no idea whether this is actually accurate since they don't cite their source. Besides, it's clearly an extrapolation.) https://www.ft.com/content/21ed4e9c-2b20-4a9d-bf38-6b76212beef8 https://www.ft.com/content/21ed4e9c-2b20-4a9d-bf38-6b76212be...

comicjk 5y ago

If we assume everyone has been infected? Why would we assume that? The estimates I've seen (including asymptomatic) are around 1/3 infected. The source you cited is from 2020, so it doesn't tell us much about today.

criticaltinker 5y ago
Yup good catch about the old source, I removed that from my comment. The source provided by animats puts the seroprevalence at 21.6% for the U.S. I think that should be a lower bound of the number of individuals who have been infected, given antibody levels wane over time (even though immunity does not necessarily wane).

nradov 5y ago

The CDC estimates that 36% of Americans have been infected. Of those, only 15% were completely asymptomatic but most had mild symptoms. https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/burden.html https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/burd...

criticaltinker 5y ago
Thanks for pointing that out and doing the math. I did some digging, here is the paper outlining the methods and data sources for the numbers on the page you linked to [1]. That paper cites two other papers used to estimate the asymptomatic proportion [2][3]. Here is a more recent systematic review [4], which estimates that at least 33% of infections are asymptomatic. And another recent paper which estimates the lower bound for asymptomatic proportion (AP) to be 37%, with an upper bound of 67% [5]. "The estimated AP varied with age, from 74% (95% CI 65–90%) for < 20 years, to 61% (95% CI 57–65%) for the 50–59 years age-group." [5] [1] Estimated Incidence of Coronavirus Disease 2019 (COVID-19) Illness and Hospitalization—United States, February–September 2020 https://academic.oup.com/cid/article/72/12/e1010/6000389 https://academic.oup.com/cid/article/72/12/e1010/6000389 [2] Estimating the extent of asymptomatic COVID-19 and its potential for community transmission: Systematic review and meta-analysis https://jammi.utpjournals.press/doi/pdf/10.3138/jammi-2020-0030 https://jammi.utpjournals.press/doi/pdf/10.3138/jammi-2020-0... [3] Age-dependent effects in the transmission and control of COVID-19 epidemics https://www.nature.com/articles/s41591-020-0962-9 https://www.nature.com/articles/s41591-020-0962-9 [4] The Proportion of SARS-CoV-2 Infections That Are Asymptomatic https://www.acpjournals.org/doi/full/10.7326/M20-6976 https://www.acpjournals.org/doi/full/10.7326/M20-6976 [5] Estimating the asymptomatic proportion of SARS-CoV-2 infection in the general population: Analysis of nationwide serosurvey data in the Netherlands https://link.springer.com/article/10.1007/s10654-021-00768-y https://link.springer.com/article/10.1007/s10654-021-00768-y
- nradov 5y ago
  Asymptomatic is kind of a fuzzy concept so the numbers will vary based on methodology. If you test positive and then have a bit of diarrhea one day is that a COVID-19 symptom or the consequences of a bad burrito? In mild cases there's no way to be sure. https://www.cdc.gov/coronavirus/2019-ncov/symptoms-testing/symptoms.html https://www.cdc.gov/coronavirus/2019-ncov/symptoms-testing/s...