I feel like there is an underlying current of frustration building and the fact that there is so much noise compared to signal doesn't help. I'm not sure what will happen if things don't start at least trending back to normal this summer. I was beginning to question the mental well being of our country before this all started. Oh boy.
Stanford U Study: covid19 Prevalence 50-85x known cases
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Last: 5 yr ago by Player To Be Named Later
Sorry if already mentioned. This guy raised an interesting question as we put the study through its paces.
Its possible many of the participants in the study were children of adult participants.
That would, of course, lead to some level of overestimation as the study would be capturing some level of intra-family spread, which isn't an analogue to general spread out in the public world.
Its possible many of the participants in the study were children of adult participants.
That would, of course, lead to some level of overestimation as the study would be capturing some level of intra-family spread, which isn't an analogue to general spread out in the public world.
Where is the paper? Anyone got a link? Search didn't bring it up. Article says not peer reviewed yet, is it available pre-print?
Same test kit as Stanford's - premier biotech. But no paper to read.
Premier biotech has to include the FDA disclaimer "Positive results may be due to past or present infection with non-SARS-CoV-2 coronavirus strains, such as coronavirus HKU1, NL63, OC43, or 229E."
It seems to me if I'm a doctor using this for any kind of study the first dang thing I do is to go find other coronavirus samples from as far back as possible and see if it is positive for those.
Premier biotech has to include the FDA disclaimer "Positive results may be due to past or present infection with non-SARS-CoV-2 coronavirus strains, such as coronavirus HKU1, NL63, OC43, or 229E."
It seems to me if I'm a doctor using this for any kind of study the first dang thing I do is to go find other coronavirus samples from as far back as possible and see if it is positive for those.
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So now we have antibody tests in Finland, Denmark, Santa Clara County, and Los Angeles in the same ballpark with population infected, and narrowing the IFR from 0.1% to 0.5%. Then we have things like the homeless population test in Boston backing it up, too.
This isn't a debate anymore.
This isn't a debate anymore.
Have you tried telling Karen that?Snap E Tom said:
So now we have antibody tests in Finland, Denmark, Santa Clara County, and Los Angeles in the same ballpark with population infected, and narrowing the IFR from 0.1% to 0.5%. Then we have things like the homeless population test in Boston backing it up, too.
This isn't a debate anymore.
The mortality rate for NYC is above the high end of what you've said... dividing deaths by all NYC residents. State-wide they're at 0.1% of all NY State residents have died (and climbing daily)
Snap E Tom said:
So now we have antibody tests in Finland, Denmark, Santa Clara County, and Los Angeles in the same ballpark with population infected, and narrowing the IFR from 0.1% to 0.5%. Then we have things like the homeless population test in Boston backing it up, too.
This isn't a debate anymore.
There's definitely a debate on some of the exact numbers and the methodology is better in some studies than others, but I agree it looks like a positive trend.
Cross posting from the politics forum:
https://news.usc.edu/168810/usc-covid-19-antibody-researcher-answers-questions-about-testing-in-l-a-county/
Two false positive out of 371 COVID-19 negative patients according to this. If that's remotely accurate, even if it's picking up some positives from the common cold virus then it's not doing much of that at all.
k2aggie07 said:
Its the same test they used at Stanford. When Stanford tried to replicate the test reported from the manufacturer, they got 63.7% sensitivity.
In the Stanford study, it is possible (unlikely! but possible) every single one of their 50/3300 positive results were false positives due to the confidence interval reported by the manufacturer on specificity.
USC is using the same test kit, with all of the same questions we have about Stanford, except we don't even have a paper to look at (like, 4.1% - is that their raw test prevalence? did they do any population adjusting like Stanford or did they get a better sample to begin with due to their recruitment method?)
And the biggest question - does this pop a positive for any coronavirus?
https://news.usc.edu/168810/usc-covid-19-antibody-researcher-answers-questions-about-testing-in-l-a-county/
Quote:
Premier Biotech, the manufacturer of the test that USC and L.A. County are using, tested blood from COVID-19-positive patients with a 90 to 95% accuracy rate. The company also tested 371 COVID-19-negative patients, with only two false positives. We also validated these tests in a small sample at a lab at Stanford University. When we do our analysis, we will also adjust for false positives and false negatives.
Two false positive out of 371 COVID-19 negative patients according to this. If that's remotely accurate, even if it's picking up some positives from the common cold virus then it's not doing much of that at all.
tests come from a company in China.....
Sure it is.Snap E Tom said:
This isn't a debate anymore.
Read the thread, plenty of good points on both sides.
k2aggie07 said:
Premier Biotech isn't the manufacturer. They're the distributor.
Dont trust China. China is as hoe.
Yeah, backtracking thru some of the secondary sources it looks like the biggest assessment of reliability probably comes from the Chinese manufacturer. USC has said that it did some of its own analysis, but the implication is that it was much smaller than the Chinese sample.
Probably need to take a wait and see on this one for now.
Dr Sood said they did the test at Stanford hospital. He was the third author on the Stanford paper, too (incestuous eh?) so I assume the USC study will reference the Stanford validation. If they used the same funny math Stanford did (100% specificity combined with 63.7% sensitivity = rate goes UP from raw not down) maybe you can cut the USC number in half. Need more tests, and hopefully not more tests with the same kit.
More good news! And makes sense. To me at least.
No material on this site is intended to be a substitute for professional medical advice, diagnosis or treatment. See full Medical Disclaimer.
dermdoc said:
More good news! And makes sense. To me at least.
That we don't have a clear understanding of the accuracy of these tests, and thus no clear picture of the validity of the claims presented? But it's good to be optimistic!
Some of you are attacking the Stanford study while ignoring what I said about the Finland and Denmark studies. Oh yeah, Sweden tested antibodies too and their results were in the ballpark. You also forgot to attack the Boston study even though that was PCR. Oh, that's right, there was the big huge Vo study just released, too.
So, Stanford, LA, Finland, Sweden, Denmark, Boston, Vo. All different tests, different methodologies, and all can be criticized in some way. And yet, they're all saying the same thing.
Go ahead and criticize and nitpick. However, when you completely ignore the body of evidence as a whole, there's a word for that - strawmanning.
So, Stanford, LA, Finland, Sweden, Denmark, Boston, Vo. All different tests, different methodologies, and all can be criticized in some way. And yet, they're all saying the same thing.
Go ahead and criticize and nitpick. However, when you completely ignore the body of evidence as a whole, there's a word for that - strawmanning.
Fair enough. But I have been saying for over a month that looking at California and Washington that this was going to be the case. Only thing that made sense to me.WoMD said:dermdoc said:
More good news! And makes sense. To me at least.
That we don't have a clear understanding of the accuracy of these tests, and thus no clear picture of the validity of the claims presented? But it's good to be optimistic!
No material on this site is intended to be a substitute for professional medical advice, diagnosis or treatment. See full Medical Disclaimer.
Yep.Snap E Tom said:
Some of you are attacking the Stanford study while ignoring what I said about the Finland and Denmark studies. Oh yeah, Sweden tested antibodies too and their results were in the ballpark. You also forgot to attack the Boston study even though that was PCR. Oh, that's right, there was the big huge Vo study just released, too.
So, Stanford, LA, Finland, Sweden, Denmark, Boston, Vo. All different tests, different methodologies, and all can be criticized in some way. And yet, they're all saying the same thing.
Go ahead and criticize and nitpick. However, when you completely ignore the body of evidence as a whole, there's a word for that - strawmanning.
No material on this site is intended to be a substitute for professional medical advice, diagnosis or treatment. See full Medical Disclaimer.
Snap E Tom said:
Some of you are attacking the Stanford study while ignoring what I said about the Finland and Denmark studies. Oh yeah, Sweden tested antibodies too and their results were in the ballpark. You also forgot to attack the Boston study even though that was PCR. Oh, that's right, there was the big huge Vo study just released, too.
So, Stanford, LA, Finland, Sweden, Denmark, Boston, Vo. All different tests, different methodologies, and all can be criticized in some way. And yet, they're all saying the same thing.
Go ahead and criticize and nitpick. However, when you completely ignore the body of evidence as a whole, there's a word for that - strawmanning.
Would love it if true. Just like in medicine, I'm ok being cautiously optimistic. But that doesn't mean we should get too confident and see things because we want to see them. And we certainly can't take some positive data as fact and go all in. Not completely anyways.
No but you can look at how the disease spread or didn't in different areas and get a pretty good idea even without the antibody tests. Seems pretty clear to this old pimple popper.WoMD said:Snap E Tom said:
Some of you are attacking the Stanford study while ignoring what I said about the Finland and Denmark studies. Oh yeah, Sweden tested antibodies too and their results were in the ballpark. You also forgot to attack the Boston study even though that was PCR. Oh, that's right, there was the big huge Vo study just released, too.
So, Stanford, LA, Finland, Sweden, Denmark, Boston, Vo. All different tests, different methodologies, and all can be criticized in some way. And yet, they're all saying the same thing.
Go ahead and criticize and nitpick. However, when you completely ignore the body of evidence as a whole, there's a word for that - strawmanning.
Would love it if true. Just like in medicine, I'm ok being cautiously optimistic. But that doesn't mean we should get too confident and see things because we want to see them. And we certainly can't take some positive data as fact and go all in. Not completely anyways.
No material on this site is intended to be a substitute for professional medical advice, diagnosis or treatment. See full Medical Disclaimer.
Can you link the actual papers and not news articles? That's the problem here, media reporting sucks. I haven't been able to find any published antibody studies except the one out of Stanford.
Also, that's not what a strawman fallacy is. Strawman is where you ascribe a view your opponent doesn't hold, then beat up on that view. I guess what you're describing would be cognitive dissonance or selection/confirmation bias.
Also, that's not what a strawman fallacy is. Strawman is where you ascribe a view your opponent doesn't hold, then beat up on that view. I guess what you're describing would be cognitive dissonance or selection/confirmation bias.
WoMD said:Snap E Tom said:
Some of you are attacking the Stanford study while ignoring what I said about the Finland and Denmark studies. Oh yeah, Sweden tested antibodies too and their results were in the ballpark. You also forgot to attack the Boston study even though that was PCR. Oh, that's right, there was the big huge Vo study just released, too.
So, Stanford, LA, Finland, Sweden, Denmark, Boston, Vo. All different tests, different methodologies, and all can be criticized in some way. And yet, they're all saying the same thing.
Go ahead and criticize and nitpick. However, when you completely ignore the body of evidence as a whole, there's a word for that - strawmanning.
Would love it if true. Just like in medicine, I'm ok being cautiously optimistic. But that doesn't mean we should get too confident and see things because we want to see them. And we certainly can't take some positive data as fact and go all in. Not completely anyways.
I think the biggest take away is there is a higher degree of infected than actual reported cases. If so, then the virus is not as deadly as we thought and much more manageable.
Whether that is 25x, 50x, or 100x. It's all of some significance.
You're going to have to run some of these through google translate. Any news outlet links are based on press releases from the institution.k2aggie07 said:
Can you link the actual papers and not news articles? That's the problem here, media reporting sucks. I haven't been able to find any published antibody studies except the one out of Stanford.
Also, that's not what a strawman fallacy is. Strawman is where you ascribe a view your opponent doesn't hold, then beat up on that view. I guess what you're describing would be cognitive dissonance or selection/confirmation bias.
Vo:
https://www.medrxiv.org/content/10.1101/2020.04.17.20053157v1
Stockholm:
https://www.folkhalsomyndigheten.se/nyheter-och-press/nyhetsarkiv/2020/april/resultat-fran-undersokning-av-forekomsten-av-covid-19-i-region-stockholm/
Denmark:
https://www.dr.dk/nyheder/indland/doedelighed-skal-formentlig-taelles-i-promiller-danske-blodproever-kaster-nyt-lys
Boston:
https://www.medrxiv.org/content/10.1101/2020.04.12.20059618v1
Finland:
https://thl.fi/en/web/thlfi-en/-/number-of-people-with-coronavirus-infections-may-be-dozens-of-times-higher-than-the-number-of-confirmed-cases
I also found:
Scotland:
https://figshare.com/articles/Serological_analysis_of_1000_Scottish_blood_donor_samples_for_anti-SARSCoV2_antibodies_collected_in_March_2020/12116778/2
Germany Cluster:
https://www.land.nrw/sites/default/files/asset/document/zwischenergebnis_covid19_case_study_gangelt_0.pdf
Thanks!!
Thanks for all those links. I love reading stuff like this.
Just a word of caution about the Boston study, though. Their study wasn't designed to determine asymptomatic spread across the population. They were simply testing to see how many people tested positive for coronavirus in a homeless shelter in the aftermath of an outbreak. They did not follow up on these people to see if they later became symptomatic. It would be awesome if they were able to do so.
Just a word of caution about the Boston study, though. Their study wasn't designed to determine asymptomatic spread across the population. They were simply testing to see how many people tested positive for coronavirus in a homeless shelter in the aftermath of an outbreak. They did not follow up on these people to see if they later became symptomatic. It would be awesome if they were able to do so.
NYC Pregnant women:Moxley said:
Thanks for all those links. I love reading stuff like this.
Just a word of caution about the Boston study, though. Their study wasn't designed to determine asymptomatic spread across the population. They were simply testing to see how many people tested positive for coronavirus in a homeless shelter in the aftermath of an outbreak. They did not follow up on these people to see if they later became symptomatic. It would be awesome if they were able to do so.
https://www.nejm.org/doi/full/10.1056/NEJMc2009316?query=C19&cid=DM90482_NEJM_COVID-19_Newsletter&bid=186123144
29 out of 215 were asymptomatic when admitted.
"Of the 29 women who had been asymptomatic but who were positive for SARS-CoV-2 on admission, fever developed in 3"
So 26 out of 215 never had symptoms.
The challenge with these studies is cross referencing it by age. We had early reports that the symptomatic attack rate was age dependent. If the asymptomstic spread is age related and not, say, genetic or some other uniform distribution that sucks. You end up with a lower IFR, but no reductions in actual deaths - actually in a way worse, because it's that much harder to control.
Thanks for the links. I'll look through them as I find the time.
If I recall, starting at the top, the Vo study found a broad majority of cases developed symptoms. It was an early indication of asymptomatic spread, but not that the virus would likely be able to spread all that "quietly." And like 1/5th of the population ended up hospitalized. Its an 8 square mile town with a known early introduction.
If I recall, starting at the top, the Vo study found a broad majority of cases developed symptoms. It was an early indication of asymptomatic spread, but not that the virus would likely be able to spread all that "quietly." And like 1/5th of the population ended up hospitalized. Its an 8 square mile town with a known early introduction.
Unfortunately none of those are papers for serological studies. There's some media reports but the papers are for swab / PCR tests, which only tell you active infections. The media reports for blood tests don't give key information like sensitivity of the test, sample size, etc.
I hate to bring bad news but there is a lot holes in the Stanford study guys. But also the test they used as specificity of only 90%. This means 1 out 10 will be a false positive but that is when you close to 100% who are actually positive when you have lets use 10% infected the false positive rate is huge. (10%*90*=9.0) So what this means if test 100 people with this test and 10% are actually infected you would have 9 false positives so 19 out of 100 will test positive with the test they used.
In addition they recruited people on facebook which would also lend towards getting more positive tests as people with recent symptoms would be more likely to go get the test done, These are just a few of limitations. We can all hope that these numbers are real so we are closer to herd immunity but most likely they are not.
We all know the denominator is much bigger we just have no idea how much bigger it actually is. We all want it as large as possible.
In addition they recruited people on facebook which would also lend towards getting more positive tests as people with recent symptoms would be more likely to go get the test done, These are just a few of limitations. We can all hope that these numbers are real so we are closer to herd immunity but most likely they are not.
We all know the denominator is much bigger we just have no idea how much bigger it actually is. We all want it as large as possible.
No material on this site is intended to be a substitute for professional medical advice, diagnosis or treatment. See full Medical Disclaimer.
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