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Preliminary test results suggest 21% of NYC residents have Covid antibodies

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Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#21

Post by rubidium »

cozzyd wrote: post #16
cm2187 wrote: post #2

Another datapoint suggesting the death rate of this virus is within 0.5%.

I had the opposite conclusion. There are between 10k-15k COVID-19 associated deaths in NYC, depending on how you count (the higher rate is consistent with the excess-mortality data, I believe). That by itself produces a range of ~0.56%-0.86% if you assume 21.2 % of NYC has been infected (larger range if you allow for some error on the infection rate, obviously). Moreover, we don't know what fraction of the currently-…

“ Moreover, we don't know what fraction of the currently-infected who will die have already died. A reasonable guess might be 50%” I lost you at reasonable guess. Why not ~1%?

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#22

Post by Avamander »

cm2187 wrote: post #2

Another datapoint suggesting the death rate of this virus is within 0.5%.

Mortality rate, case fatality rate and infection fatality rates are all different things and have different values.

Infection fatality rate of the virus could be within 0.5% (because its the one that tries to take into account everyone who has been infected), mortality rate is very likely still the one WHO has published and the third, case fatality rate is ~38% in the US.

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#24

Post by vkou »

If this study is accurate, and is not just working on garbage data, and if these antibodies actually mean long-term immunity, this means one of two things:

1. If the lockdown is lifted, we will see another ~60,000 to 100,000 deaths in NYC, before it will hit herd immunity.

2. Or, the lockdown will continue.

The accuracy of antibody studies has been called into doubt, and as far as I know, nobody has ever followed up on whether or not people with study-detected antibodies can catch the virus. The data for the latter is unlikely to be available until the second wave hits.

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#25

Post by jdm2212 »

3fe9a03ccd14ca5 wrote: post #19
ccleve wrote: post #17

This study doesn't appear to suffer from the same methodology problems as the Stanford study of a few days ago. In that study, they recruited people through Facebook, and reported an infection rate that was low enough that it could have been caused by false positives. Here, it's closer to a random sample, but more importantly it shows really high rates. Those rates overwhelm any error due to false positives. Also, it…

What's weird is that the Stanford study was suggested to have exaggerated the results, since those who suspected themselves as having the virus at one time were more likely to volunteer (allegedly). However, those results were nowhere near as big as this (I think like 2%-3% versus the 20%!)

Roughly 1/1000 New Yorkers have died of coronavirus. At a 1% IFR, that suggests at least 10% of the state has gotten the virus. Probably more, because deaths are undercounted and many people who will die of the virus already have it but haven't died yet.

In the Bay Area, almost no one has died of coronavirus so the infection rate should be next to nil.

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#26

Post by vkou »

cm2187 wrote: post #2

Another datapoint suggesting the death rate of this virus is within 0.5%.

15,000 deaths (So far) in NYC. 8.4 million people. If 20% of the population has had it, the death rate is 1%... Assuming that none of the currently infected die. Which is an unreasonable assumption (As the mean time to death from the point of infection seems to be ~2 weeks, and infections have doubled over the past 2 weeks.)

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#27

Post by rubidium »

3fe9a03ccd14ca5 wrote: post #19
ccleve wrote: post #17

This study doesn't appear to suffer from the same methodology problems as the Stanford study of a few days ago. In that study, they recruited people through Facebook, and reported an infection rate that was low enough that it could have been caused by false positives. Here, it's closer to a random sample, but more importantly it shows really high rates. Those rates overwhelm any error due to false positives. Also, it…

What's weird is that the Stanford study was suggested to have exaggerated the results, since those who suspected themselves as having the virus at one time were more likely to volunteer (allegedly). However, those results were nowhere near as big as this (I think like 2%-3% versus the 20%!)

But we already know the actual infection rate is higher in NYC than CA. The main point that the antibody tests help uncover is death rate.

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#28

Post by chrisseaton »

JamesBarney wrote: post #5

> The reason the tests were randomly taken from those at grocery and big-box stores is that these were people not isolating in their homes and presumably not at work and therefore not essential workers.

I don't understand - essential workers still going to work also have to eat, and so go to grocery shops like other people.

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#29

Post by bhouston »

3fe9a03ccd14ca5 wrote: post #19
ccleve wrote: post #17

This study doesn't appear to suffer from the same methodology problems as the Stanford study of a few days ago. In that study, they recruited people through Facebook, and reported an infection rate that was low enough that it could have been caused by false positives. Here, it's closer to a random sample, but more importantly it shows really high rates. Those rates overwhelm any error due to false positives. Also, it…

What's weird is that the Stanford study was suggested to have exaggerated the results, since those who suspected themselves as having the virus at one time were more likely to volunteer (allegedly). However, those results were nowhere near as big as this (I think like 2%-3% versus the 20%!)

NYC and standord are markably different scenarios. But in each case the percentage of baseline infection to deaths is similarish, even though the percent compared to total pop is quite different.

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#30

Post by cm2187 »

cozzyd wrote: post #16
cm2187 wrote: post #2

Another datapoint suggesting the death rate of this virus is within 0.5%.

I had the opposite conclusion. There are between 10k-15k COVID-19 associated deaths in NYC, depending on how you count (the higher rate is consistent with the excess-mortality data, I believe). That by itself produces a range of ~0.56%-0.86% if you assume 21.2 % of NYC has been infected (larger range if you allow for some error on the infection rate, obviously). Moreover, we don't know what fraction of the currently-…

0.5% comes from Cuomo’s presentation [1].

Also your 50% seems very high to me. My understanding is that 50% is about the death rate of covid patients requiring ventilation, so the overall death rate of people hospitalised for covid must be well below that.

Also if you factor this timing impact, you have the same timing impact on the denominator, i.e. people who are infected but haven't developped antibodies yet.

[1] https://youtu.be/TisDYYWJgBA?t=967

[edit] in fact for the 50%, we have an idea from Cuomo's presentation charts. The gross daily hostpitalisation rate as of 10-15 days ago was about 2000-2500 per day, and the number of death now is about 500 per day, so that suggests roughly a 20-25% death rate for hospitalised people (I am sure there must be some more precise figures somewhere).

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