What will be the big-picture implications of the coronavirus, assuming it eventually infects >10% of the world?

Yeah, I kind of wrote that in a hurry to highlight the implications of one particular update that I made (namely that if hospitals are overwhelmed the CFR will become much higher), and didn't mean to sound very confident or have it be taken as the LW consensus. (Maybe some people also upvoted it for the update rather than for the bottom line prediction?)

I do still stand by it in the sense that I think there's >50% chance that global death rate will be >2.5%. Instead of betting about it though, maybe you could try to convince me otherwise? E.g., what's the weakest part of my argument/model, or what's your prediction and how did you arrive at it?

It seems like your arguments can be summed up as "if we slow the spread enough, hospitals won't be overwhelmed" but the US only has 924,107 beds in total, and if each case takes 4 weeks to recover ("People with more severe cases generally recover in three to six weeks.") we can treat 11 million people or 3.4% of the population over a year, but that would mean death rates from other diseases would rise a lot since those patients wouldn't have beds. Many countries do have a lot more beds per capita than the US (which surprises and confuses me) but presumably they're almost all being used already?

ETA: Actually the limiting factor probably isn't hospital beds but equipment for treating respiratory disease. For example according to this paper:

The median number of full-feature mechanical ventilators per 100,000 population for individual states is 19.7 (interquartile ratio 17.2-23.1)

This works out to be about 65,000 in the whole country which is a small fraction of what's needed to treat the number of people who will need them (.05 * .5 * 327e6 = 8,175,000) even spread out over a year or two.

For many places, like the US, needing approvals is more of a problem than cost, when it comes to building new hospitals or ventilators or so on. It seems quite possible that the regulations will shift as a result of the experience here.

Do you think shorting the market is a good idea still?

If 2.5 to 10% of the world population will indeed die, I cannot possibly see how the stock market would be low right now. A global recession or depression would result and that would be much worse than where it's at now.

Is the 5-10% global mortality prediction conditional on COVID-19 infecting >10% of the world, or unconditional?

It's more or less unconditional at this point, since it's not clear what could stop the virus from infecting >10% of the world. If you watch the press conferences for the Seattle-area outbreak, the officials in charge are saying it's unlikely that they can contain it.

What do you think of the prospects for antivirals like remdesivir to be tested and mass-produced? How much could they lower CFR?

I think the prospects are good for successful test but I don't know about scaling up production. I've asked this myself in various places and have not gotten any answers.

Why do you think other predictions, such as those given by Metaculus 1, 2, 3 are much less pessimistic?

I don't have time to go through all those comments to find out where people gave their reasons. If you've read them, can you point to some that give the best arguments for their predictions? Then I can compare with my reasons...

Do you think shorting the market is a good idea still?

Yes, if my prediction is right and the market has only priced in a much lower death rate. I'm not as confident about this as I was in my original bet though. ETA: Mainly because of uncertainty about antivirals.

Notably eg the Diamond Princess number (36) isn't critical cases, but "serious/critical" cases. Do you expect 70% fatality without critical equipment for the entire "serious/critical" category, or just the "critical" sub-category?

Further, curious about if there are explicable reasons underlying your 70% estimate, cause I am trying to estimate this myself too. Notably, I've seen numbers from China that 50% of critically ill patients die *with* medical care.

From here:

The vast majority of those infected sooner or later develop symptoms. Cases of people in whom the virus has been detected and who do not have symptoms at that time are rare - and most of them fall ill in the next few days.

From here, describing Singapore:

All 84 confirmed case patients were hospitalized

10% to 20% of hospitalized patients becoming severely ill

Connect these dots, along with the fact that Singapore has been doing extremely aggressive contact tracing and has been successful enough to almost stop the spread, I think Singapore can't have many uncounted mild or asymptomatic cases, and their severely ill rate is still 10% to 20%. I assumed 20% earlier, so maybe the lower end of my estimate should be discounted by another half to arrive at 2.5%-10% overall death rate.

Just saw this just now. Basically, it's evidence that the virus has been spreading below the radar in Washington State for the past 6 weeks. People on the sub are taking this to mean the fatality rate is lower than commonly thought, since we should be seeing more hospitalizations if it truly is 20% serious. That said, I'm not sure I agree with that take -- 6 weeks of spread from 1 initial person is only ~100 people I think, and maybe 20 serious cases of influenza could go under the radar.

That seems a bit misleading because current CFR estimates are largely driven by cases from Hubei province, where the hospitals are already overwhelmed. You could argue that there’s room for things to get worse, and I probably agree with that. But I don’t see how this consideration warrants such a huge update to the CFR estimates. It seems to be already factored in to quite a large degree.

My understanding is that China sent a large number of doctors from other provinces to Hubei (can't find the source now), and the outbreak was controlled via draconian means unlikely to be reproducible in most parts of the world. Hubei has a population of 58 million and only 66907 confirmed cases, so the hospitals were not nearly as overwhelmed as they could have been.

ETA: Looking at the Imperial paper you cited, the (uncorrected) estimated CFR being 18% was not the result of hospitals overwhelmed, but undercounting infections within Hubei (see page 10), which they then corrected to 1%. So I think this is consistent with the CFR estimate being based on hospitals not being overwhelmed, and it being much higher in the future when hospitals throughout the world will be overwhelmed.

The WHO report said some 90% of people had fever. Maybe the tests have a significant false neg rate, or theyre not testing enough people, but I am worried that few mild cases are being missed.

Betting against Trump for saying something inane has proven unprofitable in the past.

As an heavy predictit user, I'm not 100% sure what's going on there either. I've already bet the max against Trump winning, and it could be a similar story for other top users. Another possibiilty is that the ongoing Dem primary is providing evidence that Trump will be re-elected, cancelling out the effect of Trump's poor coronavirus response. In particular, turnout has been alarmingly bad and Biden looks both increasingly likely to be nominated and increasingly senile.

Just speculating, but maybe the market expects Trump's germophobia to cause him to take strong action in the future?

Because prediction markets work far worse than most people here give them credit for, especially for Nassim Taleb style events.

I remain skeptical of these stories. These people are being tested with excruciatingly sensitive molecular tests after leaving severe disease in a way that is not common in other health contexts. We know that people can shed deactivated measles virus that can be detected by PCR for weeks after they recover. If I was going to guess, I would suspect that what you have is people who got a severe infection with a damaged respiratory system are then coming down with secondary complications while still shedding detectable virus, or their immune system falls apart due to severe complications allowing remnant virus to replicate up to detection levels.

It could be an indication that severe disease can produce a long lingering recovery and you're not always out of the woods when you are getting better. But the notion of people who had managed to clear the thick hot and heavy infection getting reinfected by a few hundred viral particles from outside their body again so quickly just doesn't sit well with me. If reinfection happened I would expect it to take years...

I wish news media people would stop with the 'HIV' nonsense. Sorry but it just gets on my NERVES at this point.

Every statement having anything to do with HIV goes back to a single preprint that came out a few days after the first genomes, from a lab in India that if this manuscript is any indication has a severe quantity over quality program. The SARS-CoV2 genome has a few percent difference to the SARS genome from a decade ago. There are a couple of small insertions in the protein that the virus particle uses to bind to the human ACE2 protein and gain access to cells for replication. These insertions are indeed a big piece of what makes it so infectious, it binds to human cells much stronger than the SARS virus did. This lab, though, just ran a sequence search and freaked out over the fact that there were matches to these small ~5 amino acid sequences in a few HIV genomes (and didn't talk about the bacterial and plant genomes you can also find matches in).

They neglected to report something called the 'expectation value', the number of times you would expect to find those sequences in a sequence database by random chance. It was high. Short sequences are likely to exist somewhere else in the sequence database by random chance when you dig through all the sequence database in the world, theyre particularly likely to be found in viral sequences that are biased in ther composition, and HIV in particular is something like one fifth of viral sequences on record due to all the research that has been done on it both for disease and biotech purposes and it is hypermutable. The numbers pencil out that you would be surprised NOT to find those sequences in some HIV strain in the databases somewhere. And on top of that, the similar HIV sequences they found are in bits of the HIV sequence that have nothing to do with the function of the protein the insertions are in in the SARS-CoV2 virus.

They also didn't compare the binding protein to the binding protein of any coronaviruses other than the SARS virus from a few years back. There is a wild virus sequenced from a bat that has a common ancestor with this virus about fifty years ago and has these insertions, plus or minus a few mutations.

And of course, nobody noticed that another similarly low-quality preprint noticed that a piece of one of the proteins vaguely resembled a 20 base pair piece of intergenic DNA from a fish. With a similarly high expectation value. And all the same problems but didn't get the dogpile because it didn't make people freak out.

So yes, there are insertions in the protein that are part of how this virus manages to bind incredibly strongly to the human ACE2 protein and be extremely infectious and contagious. They have NOTHING TO DO WITH HIV and I wish the news would stop parroting that preprint, which within 48 hours was dogpiled by scientists telling the authors that the conclusions about everything but the sequence itself was bullshit to the point that they published the preprint equivalent of an erratum.

I think there is plenty of events reported in (English language versions) Chinese press and reports of events showing manipulation of the data to provide lower infections and death numbers by Chinese themselves to question the numbers. The fact that there might be a China-always-lies-about-data train that any number of people might be riding really has much to do with it.

They definitely have been taking some very serious actions. However they have also been using their dominant position in WHO to craft an international narrative that may well have allowed a greater international spread of the infection.

That said, clearly the existing meme and this outbreak seem very compatible with my bit above about xenophobic reactions. I do think it's a risk, and certainly hope it does not play out, but as I said I think the end result in a few years is no one really remembers this any more than they do SARS and MERS.

[Things like this don't help the case for believing China's government. After releasing the first COVID-19 genome sequencing the Chinese lab was shutdown for "rectification" without any real explanation it seems.]