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

billiontoone.com

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

#161

Post by tvmalsv »

dvdt wrote: post #2

I'm the co-founder and CTO at BillionToOne. I'm happy to answer any questions here. I've also posted a slightly more technical explanation of how the test works and why it can scale here: https://twitter.com/dtsao/status/1247642005510873088?s=21 Edit: Since our site seems to be overwhelmed at the moment, here's a recap: We’ve been working hard at BillionToOne on a new COVID-19 test that scales testing to everyone in…

Pardon my ignorance, but does the test detect the actual virus or fragments that result from the infection?

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

#163

Post by labawi »

542458 wrote: post #127
abfan1127 wrote: post #117

Earlier quoted context omitted.

if the virus is known to live on cardboard or plastic for 48-72 hours, is the viral transport medium even necessary, assuming rapid shipping and processing?

Can live up to X hours != Will live up to X hours Let’s say it’s 50/50 whether it lives 24h without help. That’s would be a pretty bad false negative rate for your test, but a 50/50 of potentially getting infected by your mail is pretty high.

To be more precise, last info I read modeled the virus with exponential decay, with half-life measured in minutes to hours. After an hour (or 3h or 0.5h), half of the virus is already inactive¹.

Even after ~6 half-lives, remaining 1% of viral load is still potentially dangerous, but it's not a good basis for a test if you want it to be sensitive.

¹ Inactive does not mean destroyed. It may be possible or even easier to detect a partially decomposed virus, even with the current tests. Or not.

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

#164

Post by twic »

dvdt wrote: post #31
ipsum2 wrote: post #15

Earlier quoted context omitted.

Thanks for the link to the scientific manuscript. Can you speak more about the machine learning aspect? Best of luck on getting FDA approval.

"When you’re fundraising, it’s AI When you’re hiring, it’s ML When you’re implementing, it’s linear regression" The core of our machine learning is Ax=b :grins: More seriously, the main reason why traditional sanger sequencing can't be used for COVID-19 testing is because it would be unclear whether a lack of signal is truly due to lack of virus, or if it is just because the assay failed (happens all the time!) What…

> Since we know what both the reference and viral signals look like, we can perform linear regression analysis to fit the linear combination of viral and reference signals that best match our data.

Does this mean you assume a linear relationship between the quantity of viral RNA and the strength of the signal?

I know that when back i used to draw calibration curves from my positive controls, there was usually a sublinear relationship, across all sorts of different assays, at least at the upper end.

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

#165

Post by chillydawg »

billiontoone wrote: post #86
pjschlic wrote: post #79

Earlier quoted context omitted.

When you say 'as long as the end user is not financially benefitting' - is the end user the lab conducting the test? You said in an earlier comment that the reimbursement for testing is too low to justify buying expensive equipment. You are also proposing to charge half the reimbursed rate for it to run on someone else's equipment. Are the current equipment owners expected to donate this crucial equipment, because if…

$15 is half the price of even the bare minimum qPCR kits (e.g., TaqPath). We need to buy the reagents from NEB, IDT, and others and work with a contract manufacturer to mix it into a reaction. Reagent, manufacturing, quality control, and fulfillment cost already add up to ~$11/reaction. That does not take into account any costs associated with developing the assay, supporting the assay, getting it through EUA, custom…

You and your co founder(s) are good people. I'm glad you're in a position to do this. If this works, you'll save lives.

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

#166

Post by rplnt »

limaoscarjuliet wrote: post #162

Germany decided to mix 10 specimens and run a test, only then - if positive - test individual samples. They increased their testing capacity 10x (roughly) overnight. https://edition.cnn.com/world/live-news/coronavirus-pandemic...

There was a study, IIRC from Israel, which said this is still reliable with 64 samples mixed.

The next question is, do you need to test the individual samples then? Not sure how much available material for testing you have, but you might be able to just divide the mix to eliminate bigger groups first.

Or even mix parts with new samples. There must be an ideal procedure (throughput-wise) if you know how the range of positives to expect.

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

#167

Post by arcticbull »

meheleventyone wrote: post #152

I’d like to point out that schools are not open in the normal sense in Iceland. All the older kids school is stopped and Universities are shut. Our youngest is three and is in her leikskoli on alternate days so they can maintain small group sizes with no contact between them. Our eldest is six and only in school for a few hours in the morning, skips a bunch of more risky activities and is again segregated from other…

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?

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

#168

Post by thinkingemote »

arcticbull wrote: post #167
meheleventyone wrote: post #152

I’d like to point out that schools are not open in the normal sense in Iceland. All the older kids school is stopped and Universities are shut. Our youngest is three and is in her leikskoli on alternate days so they can maintain small group sizes with no contact between them. Our eldest is six and only in school for a few hours in the morning, skips a bunch of more risky activities and is again segregated from other…

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?

Or other children and their family etc.

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

#169

Post by buboard »

rplnt wrote: post #166
limaoscarjuliet wrote: post #162

Germany decided to mix 10 specimens and run a test, only then - if positive - test individual samples. They increased their testing capacity 10x (roughly) overnight. https://edition.cnn.com/world/live-news/coronavirus-pandemic...

There was a study, IIRC from Israel, which said this is still reliable with 64 samples mixed. The next question is, do you need to test the individual samples then? Not sure how much available material for testing you have, but you might be able to just divide the mix to eliminate bigger groups first. Or even mix parts with new samples. There must be an ideal procedure (throughput-wise) if you know how the range of p…

That works well for low infection rates

https://www.biorxiv.org/content/10.1101/2020.04.03.024216v1....

https://www.medrxiv.org/content/10.1101/2020.04.05.20054445v...

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

#170

Post by watwut »

buzzkillington wrote: post #60
tbenst wrote: post #10

Thanks for your efforts! Inspiring to see our broader community spring into action. I was part of a volunteer team that tested 3400 people on Friday/Saturday in Santa Clara country for COVID-19 antibodies [1]. It took a team of 100+ volunteers 10 hours / day just to collect samples. Stanford, for example, has plenty of automated testing capacity, and even reagents. IMHO, the limiting factors are not that we need new…

I find it incredible that no one has done these studies before issuing the lock down orders. Without knowing what the proportion of people who have been exposed but aren't sick any response is the wrong response. If it turns out that it's already spread to most everybody lock downs are just a way to create more homelessness. If it turns out that the only people with the antibodies are the ones in the hospitals we nee…

No response is response too. It would be incredible to done such massive studies before antibodies tests existed and organizations were able to do them on mass scale.

What they had at the time were models (which predicted asymptomatic cases) and information on how it looks like in countries that did not done measures soon enough. Even as China lied and made their numbers smaller then the were, enough was known publically and even more by secret services.

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