The Doctor Who Helped Defeat Smallpox Explains What's Coming • Hacker News Board

Re: The Doctor Who Helped Defeat Smallpox Explains What's Coming

#221

Post by alien_ » Sat, Mar 21, 2020, 7:52 PM UTC

jmull wrote: post #163

DennisP wrote: post #95

Earlier quoted context omitted.

We have plenty of flu tests. Covid-19 is also pretty distinctive on chest CT scans, if it's advanced enough to kill you. The numbers may be wrong in that article but the math itself seems straightforward. It's certainly true that we need more tests to be sure of the numbers. Here's a pretty interesting simulation from a research group at the University of Basel: https://neherlab.org/covid19/

> Covid-19 is also pretty distinctive on chest CT scans, if it's advanced enough to kill you. I guess you're suggesting that when people die of Covid-19, we'd know it and count it? That's not true. First, CT scans (and other expensive tests) are not generally performed on people who have died of pneumonia, apparently due to the flu (or other causes). Second, the radiologists reading those studies would have to train…

I expect that the number of people who die monthly for a certain condition to be relatively stable over time.

We can compare the usual number of people who die of pneumonia with the current one, and any significant difference can be attributed to this novel virus.

Re: The Doctor Who Helped Defeat Smallpox Explains What's Coming

#222

Post by marvin » Sat, Mar 21, 2020, 7:59 PM UTC

yotamoron wrote: post #138

logicchains wrote: post #56

Earlier quoted context omitted.

But how many of those people would have died anyway? Somebody over 80 has around a 10% chance of dying every year. Somebody over 80 with Corona has a 20% chance of dying, so the risk of dying is doubled.

This is an excellent point. I'm from Israel, and yesterday it was announced that the first corona victim has died. The poor guy was 88 years old, suffered from multiple background illnesses - and suffered a heart attack a few days before he died - it so happens that in addition to all of the above he had corona. Now, honestly - is this REALLY a corona victim? Now check the data from Italy - most deaths were like that…

Let's for the sake of the argument ignore all the deaths that would happen with proper care, young and old alike. A low double-digit percentage of all identified cases require hospitalization to survive. A double-digit percentage of those will die if they don't get intensive care. 40-70% of the population is expected to contract the disease this year.

It's not madness to take very strong measures to prevent that wave of hospitalizations from overwhelming the healthcare system. Most healthcare systems operate close to capacity, and people won't stop getting sick for other reasons while the epidemic is ongoing. This is the situation facing all countries with an advanced Covid19 epidemic.

But hey, it's a free market. Maybe one or two free-world countries will go on with business as usual, and we will get to see in practice whether the rest of the world was excessively careful. I wouldn't want to stake my parents' health on that when all indications say otherwise, but maybe someone else is OK with the gamble.

Re: The Doctor Who Helped Defeat Smallpox Explains What's Coming

#223

Post by alien_ » Sat, Mar 21, 2020, 8:12 PM UTC

throwaway_pdp09 wrote: post #201

NateEag wrote: post #191

Earlier quoted context omitted.

> There is in http://nrg.cs.ucl.ac.uk/mjh/covid19/#w which I said matches what I've found rather well There may be data there, but if I understand you correctly you did not have it when you made your first post. It is therefore inadmissible evidence as to whether your first post was a reasonable thing to write. > Yes he does, If you have decided you want to be an epidemiologist, or at least to learn their skillset, w…

> but if I understand you correctly you did not have it when you made your first post correct > It is therefore inadmissible evidence as to whether your first post was a reasonable thing to write. Completely wrong. I approximated the lowest part of a logistic function with e^x, which is reasonable for small values. Given it matched well with professional epidemiologists' graphs, it suggests I'm getting it approximate…

There's a quote that states that all models are wrong, some happen to be useful.

With this in mind I think we should stop nitpicking on non-specialists who try to raise awareness of this pandemic.

Yes there might be some differences from what a specialist would have done.

Due to the speed at which the situation evolves and the inability to test everyone daily there are lots of unknowns so even a specialist may not be able to give a more much precise figure, everything is going to be a rough estimate.

This is a very serious situation and it's better to err on the caution side, people's lives depend on everyone doing their part.

Non-constructive criticism of people who raise awareness will erode people's buy-in and people will die because of this.

Re: The Doctor Who Helped Defeat Smallpox Explains What's Coming

#224

Post by gvjddbnvdrbv » Sat, Mar 21, 2020, 8:15 PM UTC

devmunchies wrote: post #124

nemo44x wrote: post #53

Earlier quoted context omitted.

I think this is underrated. This thing must have been spreading since November here. I know a person who back in January acquired something like pneumonia and a bad fever, went to the hospital for awhile and tests were negative for flu, etc. doctors just didn’t know what it was. The person has COPD however. But anecdotally I’ve noticed quite a few more colleagues over the last few months out sick “with the flu or som…

> a person who back in January acquired something like pneumonia and a bad fever, went to the hospital for awhile and tests were negative for flu That’s exactly what happened to my dad in February.

Yes it was the case for many people in February. They didn't have covid. Your dad is very high risk and should stay home. The doctors in UK don't need a test to diagnose covid in a patient with pneumonia. They see it in a second on an xray because it is so distinct. The Chinese doctors said the same. So do the Italians.

Re: The Doctor Who Helped Defeat Smallpox Explains What's Coming

#225

Post by gvjddbnvdrbv » Sat, Mar 21, 2020, 8:17 PM UTC

irq11 wrote: post #171

magicsmoke wrote: post #110

Earlier quoted context omitted.

If COVID19 was spreading in the US since November then the US hospital system should have been overwhelmed by now with intensive care patients. The first infection in China was traced back to November and they were building hospitals by early February. The only places I've seen the first US infection being dated that early are conspiracies on Chinese social media that claim the origin of COVID19 to be the US instead…

”If COVID19 was spreading in the US since November then the US hospital system should have been overwhelmed by now with intensive care patients.” Or the fatality and hospitalization rates have been overestimated due to severity bias. We know this to be true, actually. We just don’t have good estimates of what the true rates are. It wouldn’t be shocking at all to find out the virus is already widespread, and only slig…

21 days to death, doubles every 2.5 days, exponential growth. Do the maths.

Re: The Doctor Who Helped Defeat Smallpox Explains What's Coming

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Post by ithkuil » Sat, Mar 21, 2020, 8:28 PM UTC

mynegation wrote: post #165

ithkuil wrote: post #82

Earlier quoted context omitted.

Often tests are not performed on a random sample of the population but only on people that are symptomatic. But not all symptomatic people receive tests. Knowing those two number (number of symptomatic people who would have qualified for a test, were it available; number of test performed) could paint q better picture.

Until recently Ontario had very stringent testing pre-requisites: 2 or more symptoms, history or travel in the last 14 days. Even then, on average, only 2% of tested people tested positively for SARS-Cov-2. In my opinion that makes the notion of much more larger population having it and not noticing due to the lack of testing, at least at this stage, highly unlikely.

Why should we assume different states have the same starting conditions?

Re: The Doctor Who Helped Defeat Smallpox Explains What's Coming

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Post by throwaway_pdp09 » Sat, Mar 21, 2020, 8:30 PM UTC

andrepd wrote: post #200

gdubs wrote: post #155

Earlier quoted context omitted.

I get that your comment is coming from a good place, because the threat of misinformation is real. But this is an “Appeal to Authority” argument. I’d rather have an informed discussion among smart people, even if they’re not experts in the specific field. I’d rather be able to weigh the input of many people. Especially in a case where the experts haven’t done a great job at communicating or understanding the severity…

>I’d rather have an informed discussion among smart people Yes, but that's the thing isn't it? We're not informed, and fitting ke^x to data doesn't make us informed. This reeks of Dunning-Kruger. I get that the intention is good, but we have to have some humility and not go all "hold on! I'll save the day!"

Original poster here.

> and fitting ke^x to data doesn't make us informed

Well, yours is an interesting post but let me ask if curve fitting doesn't make us more informed then what does? There's an update to the data for the US in the past few hours and it doesn't improve things.

I very carefully stated out my limitations, and then pointed them out again when someone critiqued my approach (see edit on https://news.ycombinator.com/item?id=22645793). I have done my best to accept my limitations, but still I get people like you hammering me.

So the question is why are we even posting anything on HN? Bottom line is what is HN for - non-factual debate, or factual debate?

I strongly get the impression that much criticism isn't based on my admittedly trite analysis but because a lot of people just don't know how to handle really bad news and are trying to blank a nasty reality. Doubly so when I'm accused of of "hold on! I'll save the day!" which is purely your invention.

Re: The Doctor Who Helped Defeat Smallpox Explains What's Coming

#228

Post by throwaway_pdp09 » Sat, Mar 21, 2020, 8:54 PM UTC

hanche wrote: post #207

throwaway_pdp09 wrote: post #104

Earlier quoted context omitted.

And I am having serious misgivings about posting it, nonetheless, many people have expressed deep concerned, and I'm doing the same, only with actual data. I made it clear the limits of my knowledge - which may still not excuse me, however I have to ask if you are an epidemiologist and if so, please tell me how to model the data better. And I don't mean randomly google up some papers to dump here and pretend you are…

You are absolutely right that the early phase of logistic growth is practically indistinguishable from exponential growth. As to what extent this observation is useful when applied to the current situation, I don't know – I am a mathematician, not an epidemiologist. But as a rough guide to aid understanding, I think it probably has some merit.

Thanks, it's nice to have an expert around! I was going to plot the divergence between the two but got seriously despondent and hit the bottle. Trying to sober up now.

May I ask, what area do you work in, numerical, discrete, logic, other?

Re: The Doctor Who Helped Defeat Smallpox Explains What's Coming

#229

Post by elorant » Sat, Mar 21, 2020, 9:06 PM UTC

hanche wrote: post #209

elorant wrote: post #107

Earlier quoted context omitted.

OK but how much larger than 2? Is it 2,5 or is it something like 5? Because the narrative so far doesn't fit the reality.

Nobody knows for sure, of course, but my understanding is that it is thought to be between 2.0 and 2.6 in the “do nothing” scenario. Which is scary big: See the Ferguson paper that I referenced in a different comment.

Thanks, will do.

Re: The Doctor Who Helped Defeat Smallpox Explains What's Coming

#230

Post by pfdietz » Sat, Mar 21, 2020, 9:24 PM UTC

mnl wrote: post #50

throwaway_pdp09 wrote: post #40

Earlier quoted context omitted.

I realise it's actually a sigmoid but an early decent approximation is an exponential, no? (edit: good catch though)

Apparently not with this when you're early. I took it seriously when a third degree polynomial fit worked too well and then suddenly didn't.

A logistic curve is indistinguishable from an exponential when you're "early". The earlier you are, the closer they are.