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I want to quickly plug TWIV here. It is an incredible podcast. I have listened to it for several years, along with its sister podcasts, and have found it incredible useful as a professional scientists and also just for the wonderful stories. The science they discuss is always good.

During COVID they have really stepped up to provide clear and well grounded information to their listeners about the pandemic. Every friday they have been releasing an episode where a doctor on the front lines of the NY pandemic has given a medical update on symptoms and treatments. Invaluable information!

> You don't even need to contact trace if everyone gets tested every day

If you have a factory capable putting out 350M tests/day (let's not even get in to logistics or the next steps), please hang out your shingle.

If not, then perhaps considering plans within the realm of possibility is a better use of time.

"If you have a factory capable putting out 350M tests/day (let's not even get in to logistics or the next steps), please hang out your shingle."

From the above mentioned TWiV podcast[1]:

"Take every manufacturing company that knows how to print paper, adapt their tools to print monoclonal antibodies on to those sheets and just start slicing it up and shipping it out. It's as easy as that, I mean, you know, I'm simplifying it a bit, but..."

And, as the host of TWiV said in an earlier podcast[2]:

"It's not undoable. If this were World War 2, you would figure out a way to do it! This is war. This is World War C19. I don't accept excuses. I got a letter from a laboratory person who said 'You have no idea what it takes to develop and execute a test, how many people, how much this and how much that..' and I said 'You're missing the point. You gotta try. You can't say why you can't do it. This is war. Let's do it!"

In fact, I believe he's actually understating the point. This disease has the potential to kill more Americans than died in all of the wars its ever been in combined, if it hasn't already. The stakes are enormous.

Let's get it done.

[1] - from about 32 minutes in to podcast 640 - https://www.microbe.tv/twiv/twiv-640/

[2] - from about 1 hour, 47 minutes in to podcast 638 - https://www.microbe.tv/twiv/twiv-638/

Paper: https://www.medrxiv.org/content/10.1101/2020.06.22.20136309v...

Op ed: https://www.nytimes.com/2020/07/03/opinion/coronavirus-tests...

This isn’t like PCR testing. It’s closer to insulin testing, in terms of the expense and difficulty of creation of the tests (and the means of interpreting the results). 350M is well within the range of possibility.

And the reward to having a reopened economy and significantly reduced death toll could justify very large investment.

If your test has a 5% false positive rate, which is considered normal, then you'll be misdiagnosed as sick on average once per month. That seems not too helpful.

If you're testing every day, the false positives and false negatives will wash out after another test or two. The more you test, the more confidence you can have in multiple consistent test results.

Abbott Labs FP rate was stated as 0.02%

https://www.statnews.com/2020/05/15/fda-says-abbotts-5-minut...

> The technology for fast pregnancy-test style tests for COVID-19 exists right now, and they could cost as little as $1 per test.

Antibody tests or antigen tests? I'm aware of that style of tests for the former but not the latter. You need the latter to do what you describe.

We can do fast, pregnancy-test-style serology now. BD is pushing one to market. 15min turn-around time.

The problem is that their % positive agreement is too low (<90%), and their % negative agreement is based on the PCR benchmark which already churns out a false negative rate of roundabout 30%.

And even their positives are only reasonably reliable (<90%) during peak symptoms. If you're pre, post, or low symptomaticity, its accuracy isnt even characterized (but believed to be low.)

Given all of the above, hyping them up is ... well, ignorant of all of the above, one hopes.

In this plan people would get tested again on the next day and the day after that and the day after that.

If you don't catch them on the very first day they have enough virus in their body to be above the test threshold, then you'll probably catch them in the next day or two anyway. Also, positive results can be verified with more reliable tests, if you want... or you could just retest with the same test some more, with every consistent result raising one's confidence in the test.

The TWiV episode goes in to detail about how if the goal is reducing the spread of the virus on a population level, then we only really care about a narrow window of infectivity, not about when people are infected but don't yet have enough virus to infect others. The cheap, quick tests they're talking about are good enough for this purpose.

They're reasonably quick. They are not cheap. $35 a pop or so. For our local elementary school, that would run ~115K a week.

The tests mentioned in the TWiV episode I'm talking about cost only $1 per test.

I suspect that’s marginal cost of production, not actual price. I’m one of the folks in charge of this exact issue for the healthcare chain I work for; we can negotiate volume discounts, but nothing that brings us from $35 to $1.

Can you add a citation for the false positives number?

The Abbott Labs test false positive rate was 0.02%, which seems totally acceptable to me

https://www.statnews.com/2020/05/15/fda-says-abbotts-5-minut...

On the other side of the equation, Mina’s point (see paper in my other comment) is that with frequent enough testing, the math of the epidemiology indicates that the sensitivity does not need to be terribly high to have a huge impact on the trajectory of the pandemic

Edit: I see now that you were talking about antibodies, not antigens, sorry

https://www.bd.com/documents/brochures/microbiology-solution...

The low %positive agreement generates false negatives, though, not false positives. False positives, for this context, would be fine.

Testing everyone every day seems unrealistic in the near term. New York's test latency is up to 7 days, which is already beyond the median time for symptoms to appear. Contact tracing would let potentially-affected people quarantine and wait for their test results while other people keep going out. Increasing the number of tests quickly would probably make the latency longer.

The test described in the podcast give results back nearly instantly. They are just less sensitive than currently approved tests, but according to the podcast that doesn't matter too much for various reasons.

> People could, for instance, get tested each morning, and be required to present their daily test results upon arriving at work

I don't think test turnaround time is this quick in the U.S.

Only because they're using the wrong type of tests.