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California’s Roadmap to Modify the Stay-at-Home Order [pdf]

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Re: California’s Roadmap to Modify the Stay-at-Home Order [pdf]

#71

Post by SpicyLemonZest »

jandrese wrote: post #23
bb2018 wrote: post #16

Earlier quoted context omitted.

I'm not too sure reinfection is as important mathematically as some think when you realize the goal will be to operate below a threshold of cases, not eliminate covid entirely.

The problem is that Covid-19 spreads extremely fast in unprepared populations. It only takes one unaware person to infect hundreds. Check out what happened in South Korea where they had the problem contained until one woman decided to go to church.

The woman went to a very large church, with over 1,000 people in the room. Such large gatherings won't be allowed for a while.

Re: California’s Roadmap to Modify the Stay-at-Home Order [pdf]

#72

Post by dsl »

djrogers wrote: post #64
joe_the_user wrote: post #32

Earlier quoted context omitted.

Really? New York current has quite a few times the casualties of all of China (10834 vs 3341) with a small population than Wuhan and the casualties haven't stopped there. New York by itself has one of the high casualty levels in the world by any measure.

Any comparison using the officially reported death toll in Wuhan at face value is of no value whatsoever.

Have you been on site in Wuhan? Collected any data? Where can we get a copy?

Re: California’s Roadmap to Modify the Stay-at-Home Order [pdf]

#73

Post by mturmon »

mdorazio wrote: post #3

Am I missing something? I don't see any kind of roadmap in here - it's just 6 generic talking points without any actual plan or timeline.

I think part of the point is that the clock does not determine when we can start to relax quarantine, it's our readiness/ability to detect and tamp down breakouts.

Re: California’s Roadmap to Modify the Stay-at-Home Order [pdf]

#74

Post by archgoon »

wtvanhest wrote: post #62
archgoon wrote: post #51

Earlier quoted context omitted.

Why should infections follow a bell curve? Shouldn't it be the derivative of a the logistic curve, which should be approximately exponential on both ends. I don't see how a quadratic should show up in the exponent; either mathematically or epidemiologically.

Does anyone have the ability to walk through these explanations in a little more detail. I'm having trouble understanding why infections would be a bell curve, or derivative of a log curve.

So the basic assumption of an exponential growth curve is: "rate of change is proportional to a population."

However, in the case of a virus, you eventually run out of population to consume; so you tweak the model to be "Let the rate of infection be the probability that a infected person encounters a non-infected person" (nicely, for a large population, this will give you the same results initially). This is, approximately, proportional to the product of the number of people who are infected times the number of people who are not infected (think back to chemical reagents and reaction rates). That is, (1-infected(t)) * infected(t). A function who's rate of change is that is the logistic function (and you can verify by taking the derivative of 1/(1+e^-t))

This is a simple model, ignores geography, ignores population change, and ignores changing behavior. It basically pretends everyone is an ideal gas molecule in a volume. But if you want to model something that "grows exponentially with a limit" it works alright.

I don't know under what assumptions the rate of change would yield a bell (normal) curve. (e^-x^2).

Re: California’s Roadmap to Modify the Stay-at-Home Order [pdf]

#75

Post by hartator »

mchusma wrote: post #67

A real plan would look like this https://imgur.com/spemOeG specifying the levels of restrictions and the metrics we will use to track the metrics. This allows people to understand what to expect the best possible. We already have huge uncertainty, we don't need to add uncertainty of government response on top of uncertainty of the virus. I think there is huge room to debate the numbers and what goes in what level, bu…

> I like many others are deeply upset by leadership from both parties, at all levels of government.

Yes, I agree. What’a really upsetting is they try to justify why less transparency is good thing. When they are using this only as way to impose their authority.

Re: California’s Roadmap to Modify the Stay-at-Home Order [pdf]

#76

Post by petsormeat »

hilbertseries wrote: post #61
dickjocke wrote: post #15

Earlier quoted context omitted.

In the live address they said that most implementations will be left to the county and local govts. The state isn't giving any specific guidance on masks, for example, leaving that to specific locales.

LA county now requires anyone entering an essential business to wear a mask.

As is Sonoma County, today.

Re: California’s Roadmap to Modify the Stay-at-Home Order [pdf]

#77

Post by SpicyLemonZest »

ajross wrote: post #33
timr wrote: post #26

Earlier quoted context omitted.

Different regions have dramatically different population densities, and don't necessarily need shelter-in-place rules. In NYC, shelter-in-place is probably the only feasible way to reduce social interactions when case-count is exploding, but in Boise, where people mostly live in detached housing and drive cars and cases are measured in the hundreds, it might be sufficient to eliminate large gatherings and shut down r…

> don't necessarily need shelter-in-place rules Is there a cite for that? Because that's not the way the data looks. Everywhere was growing with roughly the same exponent before lockdown. The numbers were bigger in NY because it grew longer pre-detection, but there's no reason to believe that everywhere else was any different. Really this disease's growth constant looks shockingly consistent almost everywhere in the…

Multiple states don't have shelter-in-place rules, but still remain very different from NY. (They still have some rules, of course; I agree it seems silly to claim that it was safe to do nothing.)

Re: California’s Roadmap to Modify the Stay-at-Home Order [pdf]

#78

Post by SpicyLemonZest »

adelHBN wrote: post #41
fasteddie31003 wrote: post #7

I personally think we need a county-by-county approach. There is a high variation of the infection at local levels. All the news is currently about how bad New York is and it's true but we're not all New York. http://www.countycovid19.com/

Thanks for sharing the link. But how do you enforce stay-at-home policies or any rigorous public health policies, in populated counties that border each other, such as San Francisco and San Mateo counties, or LA and Orang counties.

The county health officials would presumably coordinate with each other, as San Francisco and San Mateo are already doing.

Re: California’s Roadmap to Modify the Stay-at-Home Order [pdf]

#79

Post by munk-a »

djrogers wrote: post #64
joe_the_user wrote: post #32

Earlier quoted context omitted.

Really? New York current has quite a few times the casualties of all of China (10834 vs 3341) with a small population than Wuhan and the casualties haven't stopped there. New York by itself has one of the high casualty levels in the world by any measure.

Any comparison using the officially reported death toll in Wuhan at face value is of no value whatsoever.

It has value - it should just be treated very skeptically.

And, honestly, the US numbers are highly inaccurate as well due to a simply lack of an ability to test (instead of a lack of will to publish the real numbers).

Re: California’s Roadmap to Modify the Stay-at-Home Order [pdf]

#80

Post by timr »

ajross wrote: post #33
timr wrote: post #26

Earlier quoted context omitted.

Different regions have dramatically different population densities, and don't necessarily need shelter-in-place rules. In NYC, shelter-in-place is probably the only feasible way to reduce social interactions when case-count is exploding, but in Boise, where people mostly live in detached housing and drive cars and cases are measured in the hundreds, it might be sufficient to eliminate large gatherings and shut down r…

> don't necessarily need shelter-in-place rules Is there a cite for that? Because that's not the way the data looks. Everywhere was growing with roughly the same exponent before lockdown. The numbers were bigger in NY because it grew longer pre-detection, but there's no reason to believe that everywhere else was any different. Really this disease's growth constant looks shockingly consistent almost everywhere in the…

"Everywhere was growing with roughly the same exponent before lockdown."

No, they weren't. You're just asserting that this is true. There's effectively no way to know what the doubling rate was in a place like Boise before the national lockdown, because the numbers were in the low single digits:

https://covid-19.direct/metro/Boise?tab=glance

But even ignoring that...the site you're linking to shows a wide range of slopes on the per-state graph. You just think they look the same, because the log Y-axis compresses dramatic differences in scale, particularly near the origin. New York, NJ, Michigan and Louisiana are well above the diagonal line, while states like Wyoming, Montana, Vermont, Maine etc. are all well below it.

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