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Comment by joe_the_user | Hacker News Reader

This has been one major argument. The others have been: "flatten the curve - just extend the time until everyone gets it" (obvious problem, exponential growth can't work that way), "shelter in place 'till a vaccine appears" (not very practical) and "it's really not that bad, there are so many asymptomatic carriers that in the end it's not actually worse than the flu after all or at least there's nothing we can do." (not that plausible, not appealing, non-fatal cases still much worse than the flu).

I think this is the best position, however but it still needs to be argued for since it's not the only position.

Edit: Also, it looks like the US has plateaued at this point but in a situation with a fairly dysfunctional testing arrangement. It is going to be hard to argue for people to sit tight until tests are in place so I'm not terribly optimistic.

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> "flatten the curve - just extend the time until everyone gets it" (obvious problem, exponential growth can't work that way)

Just to nitpick a little here, it's more like "flatten the curve - stretch the time while everyone gets it, so we don't overwhelm hospitals". Even with exponential growth, you would rather deal with it over a longer period than have a massive spike where all services are overwhelmed.

The characteristic of exponential is that things tend to come all once. In the final double period, you get as many cases as all the other doubling periods combined.

Which is to say, you can stretch out exponential growth a lot and still not have enough. If you exponential growth from 1,000 to 1,000,000 cases over a year, the last month will overwhelm your services entirely and constitute the bulk of both cases and death.

There's a reason all those early graphs showed parabolas, not actual exponential curves, you can't even give plausible visual representation of this process, because it isn't plausible.

""flatten the curve - just extend the time until everyone gets it" (obvious problem, exponential growth can't work that way)"

Huh? One goal is to flatten the curve so that we don't have exponential growth. Another is to flatten the curve so much that, even if might still be exponential growth, the growth is slow enough for our health care systems to absorb the peak.

One goal is to flatten the curve so that we don't have exponential growth

The aim of mitigating measures is reducing the growth rate of the disease. But the mechanism of the disease is that you generally have a basic situation where X people infect at time t results R*X people at time t+1. That's fundamentally exponential process (even though you can extra factors, the process doesn't change 'till you get close to having infected everyone). If we can make R small enough, this become exponential decay, a good thing but still an exponential process. But when you do exponential growth. you have a doubling and on the last double, you get more cases than all the cases combines. So the peak is just MUCH higher than the rest of the curve and you can "flatten" a lot and still wind-up overwhelmed in the end if the growth process continues.

Sure. Yes. Of course you can flatten a lot and still wind up overwhelmed. Or, you can flatten enough that you don't.

"Flatten the curve" and "shelter in place" aren't mutually exclusive with a necessity to ramp up testing or develop a vaccine, they are just things that laypeople can be doing in the mean time to mitigate the negative effects of the virus while those other solutions are prepared.

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