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Comment by 609venezia | Hacker News Reader

Can we make millions of the tests rapidly available? I am still reading about test shortages on both coasts, even under the restricted testing regime we have been in so far.

Maybe the no-contact thermometers could be a scalable approach. Go to the bank? Forehead scan to get in. Go to the grocery store? Same. At least until--and maybe even after--we can scale the RNA testing.

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> Maybe the no-contact thermometers could be a scalable approach. Go to the bank? Forehead scan to get in. Go to the grocery store? Same.

This is the reality in China. Literally every single public place have a remote thermometer they scan on your forehead. supermarket? scanned. subway? scanned. restaurant? scanned. If you have a fever you'll go into quarantine in no time.

People can take ibuprofen prior to going shopping.

People can do a lot of things. It's not a big deal that measures won't be perfectly effective - in the presence of any suppression measures, once the case count stabilizes, there's a lot of room between "literally impossible to spread the virus" and exponential growth.

That's nice, but one such person can shut down the entire production line in some factory, or the hospital department. (happened already in my country) Such people have disproportionate effect on the economy.

Get IDT or (other nucleotide synthesis company) to start mass producing the detection primers, and ship them to their whole active customer catalog, they all have thermal cyclers. Then figure out the other reagents needed to locally produce tests that trade off false positive rate for the lowest false negative rate you can get. How to get swabs to the closest lab with a thermal cycler, no idea, but we have phones with gps. Rate limiting step here is probably the step from swab to sample ready for amplification. I kind of wonder if it makes sense to tell people to start swabbing now and keep the swabs in the freezer until testing comes online so that we can start filling in the missing data.

I really feel like you guys are ignoring a lot of the difficulties in ramping up production to nation scale for this hypothetical test. A "rapid" test no less. These things are not as easy as everyone is making them out to be. Making one? Simple. Scaling that up to 8 figures worth? Not so simple. A lot of us are being a little too Jedi hand-wave-y about this issue.

And think about it, I'm only talking about getting up to 10 mil or so here. We'd need a lot more than that to implement the plans being proposed on this thread. Logistics really does demand that medical personnel, and emergency responders be tested regularly to ensure their continued fitness for purpose under such schemes. Consider, there are right around 12,000 law enforcement officers alone in Washington state. Not counting doctors, nurses, EMT's and firemen. (And lest we forget the most important emergency worker of all right now, the Walmart stock boys.)

Add all that up. Multiply it by 50 states, some much larger than Washington. Under the plans you guys are proposing, we'd need multiple tests as the crisis goes on for each of these workers to make sure they aren't out infecting citizens when they interact with them. (Or when they put food on shelves that a customer picks up 4 hours later.)

Please, try to be reasonable. Maybe the current approach is not tenable, but the ideas being proposed on this thread are problematic as well.

Aren't there multiple existing labs all over the country who do this regularly? Are these tests made in small batches or something? Do you need to grow viral cultures? What exactly is the limit here and why can't a typical lab just double production in a few weeks by doubling it's hardware?

You don't have to culture anything (if we did we might as well just give up). We use PCR to amplify a known section of the viral genome. With the oligo production capacity in this country alone we could synthesize enough primers test everyone in the country 10 times in a couple of days. That is not the limiting reagent. The limit is either sample prep or sample collection. Actually running the amplification shouldn't be a bottleneck, there are hundreds of thousands of thermal cyclers across the country. In my more cynical moments I might say the bottleneck is that some companies might want to make money from all the tests ....

Yes I am also cynical about the situation. There is something not insurmountable standing in the way.

I'm trying to learn a bit more about how testing works. Aside from the logistics (getting the samples to the lab, etc), what are the necessary steps for sample prep? Heating to inactivate the virus? Splitting the sample into RNA/DNA/proteins?

Also, where do you draw the numbers of primer production capacity from? IIUC, the only other things that an amplification needs are enzymes (just DNA polymerase for PCR) and "food" (nucleotides), but that I assume is not a bottleneck?

How difficult is it to safely dispose of amplified samples? Can you basically just dump them in the toilet?

Well, figuring all that out sure seems a lot more fun than sitting and waiting. I take dying trying to do something useful over just dying.

Like in war profits will probably be huge but if there is enough pressure government cna seize stuff too.

Asymptomatic transmission is the key here. It's why "stay home if you're sick" or denying entry to detectably sick people isn't enough.

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