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kander - n may be as high as 80%
Antibody tests seem to be more important of testing factor.
I think you meant that n (the total number of cases) may be 50x - 80x (5000% - 8000%) higher than the confirmed cases. The percent of residents testing positive for having antibodies for covid is still about 3% (2.5% - 4.2%). Given an R0 or 2 - 3, a population needs 50% - 66% recovered individuals for "herd immunity" to kick in.
http://archive.is/9aDP8
"The researchers found that the percentage of infections was indeed vastly larger than the roughly 1,000 known positive cases in the county at the time of the study. The preliminary results—the research will now undergo peer review—show that between 2.5% and 4.2% of county residents are estimated to have antibodies against the virus. That translates into 48,000 to 81,000 infections, 50 to 85 times as high as the number of known cases."
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quote: Originally posted by PaulW
Whoa, you're right, forgot the numerator:
0.95 * x /
(0.95 * x + 0.05 * (100 - x))
Sorry for the mistake!
Yes, so a 37% chance it's a true positive while at first glance one would think it's 95%. Quite the paradox.
I think it would be 95% if number of actual positives in population is equal to or greater than number of negatives.
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quote: Originally posted by ironyak
50 to 85 times as high as the number of known cases."
If that were true nationwide then the approximate death rate to date from Covid19 would be more in line with estimates for the flu, correct?
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"If that were true nationwide then the approximate death rate to date from Covid19 would be more in line with estimates for the flu, correct?"
What people call "the flu" are people who have symptoms. COVID-19 is the nomenclature for people who have Sars-Cov-2 who have symptoms significant enough to be documented. Sort of how HIV and AIDS are two different things. I'm not aware of any studies about people who carry/spread influenza that are asymptomatic.
Covid19 would be more in line with estimates for the flu, correct?
I still have one problem with this... I have never seen the flu overwhelm our healthcare system before. That little fact is inescapable. Try as I might I can't find any model that minimizes this as more in line with estimates for the flu and still accounts for the ICUs being overwhelmed and field hospitals built and hospital ships afloat and freezer trucks and PPE being in short supply and did you see the headline about Spain's military starting to do massive aerial spraying of disinfectants over cities?
https://www.zerohedge.com/health/spain-a...ver-cities
No, I still have a hard time figuring how that is in line with estimates for the flu. But please don't get me wrong, I would love it if it did, but then why is Andrew Cuomo on TV every morning?
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I have never seen the flu overwhelm our healthcare system before
Please.
Must we spoil our talking points and conspiracy theories with real world examples?
"I'm at that stage in life where I stay out of discussions. Even if you say 1+1=5, you're right - have fun." - Keanu Reeves
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quote: Originally posted by hokuili
Covid19 would be more in line with estimates for the flu, correct?
I still have one problem with this... I have never seen the flu overwhelm our healthcare system before. That little fact is inescapable...
For sure.
I just divided current given mortality rate of coronavirus by 50-85 and came up with a number that was about the same as I've seen assigned to flu. Good chance my memory is faulty though.
Coronavirus in real time definitely looks to be worse than flu in both mortality and contagiousness.
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terracore - I'm not aware of any studies about people who carry/spread influenza that are asymptomatic.
I hadn't really thought about this, but it appears there have been some past studies that show many cases of the flu are asymptotic and may be contagious.
https://www.npr.org/sections/health-shot...ve-the-flu
"But just because you don't exhibit these symptoms, it doesn't mean you don't have the flu, researchers say. And you could be just as contagious. In fact, their study found that roughly three-quarters of people with seasonal or pandemic flu show either no symptoms or mild ones that aren't usually linked to flu."
...
"But this study should not be taken to mean that the flu is as trivial as the common cold." (it's not just a cold bro)
So if there are many asymptotic cases of the flu, then its CFR would also be lower, so even if covid ends up near 0.1% CFR that too might be 10x worse than the flu? (still not just the flu bro)
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Scenes on Oahu, Waikiki Beach, Ala Moana, etc before COVID-19 and after.
Sliding tool:
https://www.civilbeat.org/2020/04/heres-...-tourists/
"I'm at that stage in life where I stay out of discussions. Even if you say 1+1=5, you're right - have fun." - Keanu Reeves
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So check it, let's work together before he comes back. He'll never know, right? Yeah, just add this to that vast list of stuff he doesn't know and stuff he doesn't know he doesn't know - he'll be none the wiser...
Here's a tip - the actual answer, without Bayes, is 0.88. The whole point of the exercise is to show that the naive answer of 0.95 is incorrect and you need to know the fraction of the population that is infected before giving an actual answer. The only case where the answer is 0.95 is when 50% of the population is infected, as PaulW and Durian Fiend pointed out (apologies if someone else pointed that out and I missed it - all the insults muddied the thread).
I'm glad that at least some tried the exercise and realized what the problem really meant. Not so many thanks to those who posted insults. Guys, you can express the answer as an equation. That's what scientists generally do.
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