How have they established this has been due to testing rather than something else?

Testing and tracing are core parts of both SK's and Singapore's strategies who had cases in their countries and seem to have beaten it. I don't think we'll ever be able to proof with 100% certainty that their strategies worked because and it wasn't good luck or some other unknown factor, however it seems highly likely given the same strategy is working out well on two different places.

South Korean foreign minister believes it's testing that was key: https://www.bbc.com/news/av/world-asia-51897979/coronavirus-...

Singapore was hit hard by SARS. They adjusted their strategy and are successful with COVID-19. paper: https://academic.oup.com/jtm/advance-article/doi/10.1093/jtm...

Maybe they were just lucky, but if it was my decision, I'd put my money on the strategy that worked in those two countries and minimized cost in lives and economic impact.

Thanks for the links! To be clear, I'm not suggesting they had good luck or anything like that. I'm not even saying testing would be unhelpful (obviously it'd be helpful at least in some cases). I'm trying to figure out if there's more to the story, and if the effect testing itself is really as big as people imagine. Note that in the video she says testing is important because it minimizes further spread and quickly treats those found with the virus. But, for example, I'm hearing many Americans aren't exactly heeding the shelter-at-home orders. Would testing change that? And is there no other way to already change that without testing? Or for example, I'm hearing the US is running low on masks (not sure about other supplies) which I presume would harm patients' treatment. Would testing change that in any way? And like I mentioned elsewhere, the US can't legally just collect GPS data on everyone, and if we tried to put known cases on a map for everyone to look at, I'm not sure how well it would fly here. So are these going to be bigger obstacles to tracing even if we test people? Is testing really our biggest obstacle here?

I find these “devil’s advocate” perspectives a bit trying at times - yes testing would lead people to stay at home (since we could simply post a cop outside), yes testing would reduce PPE use (we would reduce transmission before a new case ever could walk in the ER door). You don’t need GPS data to do contact tracing.

Really, there’s no excuse for the abysmal US testing regime. We’re beyond a point where contact tracing is feasible, but there is no reason we had to get to this point.

Maybe instead of looking for excuses we should look at what they have done that can be applied to the US and Europe.

That's literally what I'm asking. What else did they do besides testing? My understanding is they've been aggressively quarantining people and tracing their contacts via phone GPS tracking, credit card data, and video surveillance [1], which is what really matters. Whereas in the US, they're telling people that testing them wouldn't change the health provider's response, which would be that the patient should self-quarantine if able. Now I don't like this fact, but I don't see why they would be lying about it. And if we assume they're not lying, then testing really would seem pointless. The problem here (as far as I can tell) seems to not be the presence or lack of testing, but the inability and/or unwillingness to provide the same kind of response in the US as in South Korea.

[1] https://www.businessinsider.com/coronavirus-south-korea-spre...

I think the problem is bigger. We can't do now what SK is doing. They are tracing cases and aggressively quarantining everyone who tests positive. Obviously you cannot do that if you cannot test enough people to get a complete enough picture of the invected population. We also probably now have too many infected to make that strategy workable at this point, even if we had the tests, tracing probably would be the new bottleneck.

This great write-up suggests to shut everything down to get cases back to a manageable level and then move to the SK and Singaporean model: https://medium.com/@tomaspueyo/coronavirus-the-hammer-and-th...

Strongly recommend the read.

I don't really think we disagree on the overall picture to be honest. I realize they're probably doing something (or I should say multiple things) right, and I realize the US has had organizational failures and such. I'm just not clear on what exactly having testing capability would let the US do that it otherwise cannot do right now, and I've yet to see a direct answer to this. If healthcare providers are saying that they'd just tell anyone who might have the disease stay home, then how does testing change the picture? Can't they do it already? Or is the idea that people would only obey this if they actually tested positive? And for tracing, can the US even use GPS etc. data the way South Korea can to trace their contacts, and invade people's privacy just like that? Would testing make that noticeably easier, compared to (I don't know, just thinking aloud) making medical providers report those that call about an illness so their contacts can be traced? etc.