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We’re working on 1M Covid-19 testing capacity per day

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Re: We’re working on 1M Covid-19 testing capacity per day

#211

Post by dwild »

timerol wrote: post #208
gnulinux wrote: post #203

Earlier quoted context omitted.

Currently in the US ~85% of tests turn negative. If sample turned positive you'd perform 10% more tests (1 extra test for each 10 tests) i.e. x1.1. If it turned negative you'd perform 10% the tests you'd normally perform without this scheme i.e. x0.1. In this case .85 of tests would be .1 of what they're now. The rest of .15 will be 1.1 of what they're now. So if US did this, they would be testing ~x.3 of their curre…

This isn't accounting for combinatorial math. If each sample is negative 85%, then the probability that all 10 samples are negative is 0.85^10, or about 20%. If any sample turned positive (the other 80% of the time), then all will need to be retested. Instead of 1 test per sample, you're now running 0.2 * 0.1 + 0.8 * 1.1, or about 0.9 tests per sample. You've increased throughput by 10%, but not nearly as much as was…

What if you consider external factors too? You can have a simple survey asking whether they have been traveled recently, whether they have symptoms, whether they are essential workers, if they know somebody that was infected, where they are living, with how many people, etc... You can easily use theses answers to remove the ones most likely to test postive with theses answers.

If you include that your goal is to test everyone too, I have no doubt that you can easily reach 96% negative test quite easily.

I remember in Quebec while we were only testing people with symptoms and that had traveled (or have been in contact with someone that has been tested positive), we were still way higher than 90% of negative tests (even right now we are a 90.1%

Re: We’re working on 1M Covid-19 testing capacity per day

#212

Post by standardUser »

yters wrote: post #196
JamisonM wrote: post #98

Earlier quoted context omitted.

Iceland has only tested 28,992 of its residents as April 6th, so that throws the rest of this conjecture out the window. (Although regardless the conjecture was probably not a great idea.) https://covid.is/data

The point is Iceland has the best statistic on death rate due to comprehensive testing.

Iceland may have the best statistic on their death rate from this virus, but these things are not static and depend on a zillion factors (slight exaggeration).

Re: We’re working on 1M Covid-19 testing capacity per day

#213

Post by zepto »

mrkurt wrote: post #101
zepto wrote: post #84

Earlier quoted context omitted.

You are downplaying the value by saying they will be useful in the future, rather than now. This is not so. They are valuable right now.

For what? "Google for answers" isn't very helpful. It sounds like they're saying serological tests are valuable, but not viable for immediately testing a large population.

Answering questions about immunity is absolutely critical right now.

https://www.newscientist.com/article/mg24532754-600-can-you-...

https://www.ksbw.com/article/new-study-investigates-californ...

Re: We’re working on 1M Covid-19 testing capacity per day

#214

Post by JamisonM »

yters wrote: post #196
JamisonM wrote: post #98

Earlier quoted context omitted.

Iceland has only tested 28,992 of its residents as April 6th, so that throws the rest of this conjecture out the window. (Although regardless the conjecture was probably not a great idea.) https://covid.is/data

The point is Iceland has the best statistic on death rate due to comprehensive testing.

I think the real point is that your original claim was a small sample that you were extrapolating wildly from turns out to be 10x smaller than you claimed.

Furthermore you are focusing on a tiny portion of available data instead of all that is available.

Given that New York State has 4,000+ deaths your "model" would indicate that 1MM residents have COVID-19? So if it rips through the remaining 19MM residents in the course of a few weeks the result will only be 80k deaths? And of course the healthcare system won't break down?

Also you said that the Diamond Princess only had a 20% infection rate but the Greg Mortimer is reporting a 60% infection rate. Seems like you've got a lot of facts wrong on the first pass, IDK.

Re: We’re working on 1M Covid-19 testing capacity per day

#215

Post by yters »

standardUser wrote: post #212
yters wrote: post #196

Earlier quoted context omitted.

The point is Iceland has the best statistic on death rate due to comprehensive testing.

Iceland may have the best statistic on their death rate from this virus, but these things are not static and depend on a zillion factors (slight exaggeration).

It is close to the other country with a lot of testing, South Korea.

Re: We’re working on 1M Covid-19 testing capacity per day

#216

Post by yters »

JamisonM wrote: post #214
yters wrote: post #196

Earlier quoted context omitted.

The point is Iceland has the best statistic on death rate due to comprehensive testing.

I think the real point is that your original claim was a small sample that you were extrapolating wildly from turns out to be 10x smaller than you claimed. Furthermore you are focusing on a tiny portion of available data instead of all that is available. Given that New York State has 4,000+ deaths your "model" would indicate that 1MM residents have COVID-19? So if it rips through the remaining 19MM residents in the c…

It seems that 'all available' would diminish the signal of Iceland's good stat. What we really want is 'all good stats'. I think only South Korea is the other country with extensive testing.

According to my model NYC should only have a max of 13.5k deaths, without any mitigation.

Based on the Greg Mortimer stat, this bumps up to 41k for NYC.

Re: We’re working on 1M Covid-19 testing capacity per day

#218

Post by Izkata »

Blahah wrote: post #205
vrinstan wrote: post #185

Earlier quoted context omitted.

What is a complete lockdown? Food workers don't go to work anymore?

In SA right now I believe everything is closed to a much greater extent than most other places. For example, restaurants are not allowed to even deliver food. Only ingredients for preparing meals at home can be delivered by grocery stores. No alcohol or tobacco. Aggressive policing of the rules.

> Only ingredients for preparing meals at home can be delivered by grocery stores.

So they're also closed to in-person shopping?

Re: We’re working on 1M Covid-19 testing capacity per day

#219

Post by meheleventyone »

zelos wrote: post #189
arcticbull wrote: post #167

Earlier quoted context omitted.

Interesting, children are at basically zero risk (no child under 10 has died). I assume they don't want to spread it between parents via children?

For primary age children at least, though, there will be roughly one parent/carer per child gathered outside the school gates, which has to be a major source of adult transmission.

Here we are all standing well apart and the kids are let out one classroom at a time.

Re: We’re working on 1M Covid-19 testing capacity per day

#220

Post by roosterdawn »

yters wrote: post #202

Is it possible to create an at home cov2 test with a $25 homemade PCR https://hackaday.io/project/27623-coffee-cup-polymerase-chai... and some synthetic DNA derived from cov2 (seems to cost about $0.09 per base pair)? https://www.twistbioscience.com/products/genes

Wow, very cool idea. While obviously this wouldn't be a substitute for lab grade testing, what makes me excited is that it could make sense as something folks produce for themselves as a precursor to getting a proper test done.
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