Preliminary test results suggest 21% of NYC residents have Covid antibodies • Hacker News Board

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#431

Post by CodeWriter23 » Thu, Apr 23, 2020, 10:16 PM UTC

ineedasername wrote: post #315

CodeWriter23 wrote: post #182

Earlier quoted context omitted.

I argue there is inherently less sampling bias in this study than testing people at the hospital who have shown up due to severe symptoms.

Those are the people who constitute the denominator for the CFR. It's a completely different metric. You would never try to impute population exposure from such cases. This study is trying to to impute population exposure. There isn't any comparison between the two in terms of which has more/less selection bias, they are completely different things.

Didn’t stop the news media from tabulating a death rate based on hospital cases alone.

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#432

Post by kgwgk » Thu, Apr 23, 2020, 10:16 PM UTC

TheBlight wrote: post #340

kgwgk wrote: post #99

Earlier quoted context omitted.

But the number of deaths does not agree.

Can you elaborate?

Percentage of people with antibodies is similar (if you take those studies at face value).

Percentage of people dead is not.

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#433

Post by CydeWeys » Thu, Apr 23, 2020, 10:17 PM UTC

TheBlight wrote: post #413

Karrot_Kream wrote: post #401

Earlier quoted context omitted.

> Sure all of these studies are potentially flawed but they're all generally pointing in the same direction That's unfortunately not the way statistics works. Combining multiple bad tests just makes the results incorrect or highly uncertain; the devil often is in the details. The Stanford/Santa Clara County study is a good example of how the details can really undermine a study. Things do indeed seem to be converging…

We don't have perfect studies and perfect data but calling these tests "bad" seems slightly unfair. They give us an imperfect but useful snapshot of what's going on. But thanks for the condescension. I'd expect nothing less on HN.

The study is dramatically over-sampling exactly the people who have the most potential exposure to COVID-19, and dramatically over-sampling the people who don't.

This could easily be way off. It's not testing the people who aren't home at all, and it has a low chance of only testing the people who leave home rarely, only when strictly necessary. It's mainly finding the people who leave home a lot.

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#434

Post by __blockcipher__ » Thu, Apr 23, 2020, 10:20 PM UTC

mlyle wrote: post #403

__blockcipher__ wrote: post #387

Earlier quoted context omitted.

At this point people advocating the position you’re advocating for are in a state of denial (this is my opinion, not a matter of fact, obviously). Your assumption is that we can effectively prevent the majority of the nation from exposure via lockdown. Not only does evidence seem to point against that, but when you do the math on mortality due to suicide and overdose it’s not clear that containment would even save mo…

Hey, I'm in broad agreement with you, but, a nit ... > Here’s how you can tell people’s philosophical positions: if they talk about fear of a “second wave” they are Containers, since that implies the initial “wave” will not infect the majority; ie the virus is successfully contained. Here in the SF Bay Area we pretty effectively blunted the first wave with public health controls, which meant health care was not stres…

So, that's definitely a good point to raise. I agree and should have been more clear. I think there should not be a second wave because I think we need to resume more or less normal society and let people naturally get exposed (since voluntary self exposure will not ever be tenable in the US I fear).

But given the way that California aggressively locked down early into this, I agree that we have been sloping down and thus there is guaranteed to be subsequent waves.

Basically, the waves are real but are arbitrary and are caused by our own misguided interventions.

> We need to figure out how to loosen up controls in a way that provides economic benefits, keeps a nice constantish burn towards herd immunity, but with enough safety margin to prevent catastrophe that New York got too close to.

100% agreed. Now the argument I do somewhat agree with is that it's very hard to get that balance right when dealing with exponential transmission. Which is why on balance I'm leaning much more towards "we'll cross that bridge when we get there" (because the alternative is that we have to stay permanently locked down).

Also the portion of the population I am advocating should be allowed to return to work is precisely the portion of the population that produces very low hospitalization rates.

I strongly believe that anyone who has been reading CNN the last few weeks would be _shocked_ to learn that we get 1 hospitalization for every 500 20-29 year olds infected (and again, these numbers are not fully settled but they're at least in the right order of magnitude IMO)

> There's a loud contingent advocating what would effectively be permanent controls.

Yup, this is what has me really scared. The widespread belief being that it is actually plausible to avoid ever getting infected and therefore any infections that follow a softening of lockdown introduce deaths that never would have occurred in the hypothetical alternate universe.

--

So, thanks for raising that point, I fully agree. The TL;DR is that implicit in "we need to watch out for the second wave" is the notion that "we need to fight these waves and halt their spread" which I strongly disagree with.

EDIT: And just to be clear, if we "re-open" we'll still all be wearing masks and keeping arbitrary distance between each other so it's not like we're all running around exchanging bodily fluids willy nilly. But I really do think that the shutdown has been, in some part, effective in curtailing spread, and thus naturally I would expect a higher infection rate following a re-opening.

EDIT 2: Removed the part about the political leanings of those advocating for long-term lockdown because it's going to set off people's defense mechanisms and potentially cause them to draw the wrong impression of what I'm saying

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#435

Post by kgwgk » Thu, Apr 23, 2020, 10:21 PM UTC

toufka wrote: post #399

kgwgk wrote: post #99

Earlier quoted context omitted.

But the number of deaths does not agree.

There also appears to be a difference in the strains. The NYC strain seems to mostly come from the European branch, while the CA infection comes directly from China (and likely much earlier in 2020). There appears to be some difference in virulence between the strains. https://www.medrxiv.org/content/10.1101/2020.04.08.20056929v... and https://nextstrain.org/ncov/global

I’ve never looked into that (I know of the hypothesis, though) but IFR in South Korea also seems to be around 1% (or higher), not 0.1%

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#436

Post by makomk » Thu, Apr 23, 2020, 10:24 PM UTC

zaroth wrote: post #367

kgwgk wrote: post #177

Earlier quoted context omitted.

> mortality is much less than previously suspected Mortality remains pretty much as suspected already two months ago: “Based on these available analyses, current IFR estimates10,11,12 range from 0.3% to 1%. Without population-based serologic studies, it is not yet possible to know what proportion of the population has been infected with COVID-19.” https://www.who.int/docs/default-source/coronaviruse/situati...

Two weeks after that the WHO released a widely cited report claiming a fatality rate of 3.4%. “Globally, about 3.4% of reported COVID-19 cases have died. By comparison, seasonal flu generally kills far fewer than 1% of those infected.” https://www.who.int/dg/speeches/detail/who-director-general-...

Yes, and then almost the entire US press spun the 3.4% figure as the real WHO-confirmed fatality rate and sub-1% numbers as a Trumpian lie as part of a stupid, cynical, partisan attempt to get Trump. There's been a lot of that. (The UK press, meanwhile, happily quoted the 1% figure - if I remember rightly, some outlets like the Guardian with both UK-facing and US-facing sides pushed both narratives to different audiences at the same time.)

In reality, the WHO number was just confirmed deaths divided by confirmed cases, which was of course almost completely meaningless.

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#437

Post by rallison » Thu, Apr 23, 2020, 10:24 PM UTC

glofish wrote: post #39

Well, it looks like in the end that much-criticized imperial model might be right on transmission rates but way off on the fatality rate and with that predicted deaths. It pretty much looks like none of the epidemiological models are reasonably accurate on both, case numbers and fatally rates

If the results from this NY study hold, the numbers are basically exactly in line with the Imperial College study. That study assumed an IFR of 0.9%, and the NY results imply an IFR right around that.

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#438

Post by scythe » Thu, Apr 23, 2020, 10:25 PM UTC

jnbiche wrote: post #374

TheBlight wrote: post #348

Earlier quoted context omitted.

Sure all of these studies are potentially flawed but they're all generally pointing in the same direction. There are many more infections than we know about and the CFR is not anywhere close to the actual IFR. NYC is an outlier with a 21% infection estimate but for the rest of NY (outside NYC metro/Westchester/LI) the estimate is 3.6%. Santa Clara estimate was 3%. LA County estimate was 4%. Seems like a trend is deve…

The CFR will be much higher than the IFR. For example, approximate flu IFR is 0.05%.

In comparing the COVID-19 IFR to the flu IFR, it is important to remember that flu vaccines are widely available and limit the spread of influenza. For example, CDC retrospectives for 2018-9 estimate that 35M Americans[1] got influenza over the flu season, or less than 12%.

By contrast, the current COVID-19 infection rate in New York (from these data) is already higher than 12%. So COVID-19 has the potential to infect a larger proportion of the population than the flu usually does.

(If the CDC data is correct, the flu shot may save around a hundred thousand lives per year. Don't skip it!)

1: https://www.cdc.gov/flu/about/burden/2018-2019.html

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#439

Post by __blockcipher__ » Thu, Apr 23, 2020, 10:28 PM UTC

slg wrote: post #410

__blockcipher__ wrote: post #387

Earlier quoted context omitted.

At this point people advocating the position you’re advocating for are in a state of denial (this is my opinion, not a matter of fact, obviously). Your assumption is that we can effectively prevent the majority of the nation from exposure via lockdown. Not only does evidence seem to point against that, but when you do the math on mortality due to suicide and overdose it’s not clear that containment would even save mo…

I agree with some of what you said here, but there is one specific point I want to disagree with. All the projections for unemployment related deaths are based on society functioning as it previously did. I think many of the people who are suggesting we are in for long term isolation are also suggesting a much bigger increase in the social safety net to help people through these difficult times.

Right, but I think some of that suicide rate comes from the lack of "purpose" (it's silly that we rely on our jobs for purpose but we really do), or more broadly the desynchronization of one's internal schedule that many of us have experienced (which leads to worse sleep and therefore higher mortality).

I also think that given we know about the level of competence of our government, it will be very difficult for "real" safety nets to be put into place. That's not even getting to the partisan divide inherent to our system.

So in my eyes, we had one big problem, covid, and turned it into two big problems, covid and an economy in ruin. And these two problems affect a greater set of individuals than either one alone. Since a huge number of deaths from Covid are those who weren't working because they're 70+.

Lastly, one of the most "famous" social safety nets in America is social security, which is a farce that is known to redistribute money from the poor to the rich. (It is an eternal frustration of mine that the Left in America is so heavily in favor of social security despite it being flawed from its inception) [1]

[1] See Milton Friedman's excellent take https://www.youtube.com/watch?v=rCdgv7n9xCY

Re: Preliminary test results suggest 21% of NYC residents have Covid antibodies

#440

Post by cozzyd » Thu, Apr 23, 2020, 10:31 PM UTC

mmastrac wrote: post #209

izend wrote: post #198

Earlier quoted context omitted.

Making it the worse pandemic in decades but no where near the Spanish Flu.

Hard to compare directly against the Spanish Flu as medicine has had 100 years of progress, but assuming you are talking about overall impact, agreed.

The age distribution was also significantly different then.