Comment by usaar333 | Hacker News Reader

Comment by usaar333 | Hacker News Reader

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It is not plausible they caught most cases.

Here's the result of randomized testing in Iceland, which also has the virus under control and has done even more testing per capita (https://www.nejm.org/doi/full/10.1056/NEJMoa2006100?query=fe...)

Randomized testing was still finding 0.6% of the population (outside those otherwise quarantined already) actively infected. This means even in Iceland, less than half of infections were being caught.

Iceland's CFR right now is 0.74% using deaths/recovered (or if you use an ultimate 20% hospitalization fatality rate, around 0.87%). If they missed half of infections, you get an IFR down to under 0.5%, though I'll admit they are doing better by keeping their most vulnerable population from being infected. (note the low infection rate for people 70+ at https://www.covid.is/data).

So no, not an order of magnitude lower, but 3x lower (0.7%) is looking pretty reasonable. Imperial College's latest estimate is 0.66% for China (https://www.medrxiv.org/content/10.1101/2020.03.09.20033357v...).

That's a much more reasonable interpretation of the available data, although there are still plenty of unknowns here, as sibling comments are pointing out. My interpretations the last week are converging on the same ballpark figures.

I'd just like to point out that this is still a far cry from the wishful thinking a lot of people are putting forth, claiming an IFR of < 0.1%, that 30% of the population have already had the disease and that herd immunity is both imminent and feasible.

These interpretations seem less likely to be true today than they did two weeks ago, and even then they were making assumptions on the optimistic side.

An IFR of 0.5% and a hospitalization rate in the high single digits is still a big frickin problem for society, when the disease has a reproduction number greater than 2 (and in the absence of countermeasures, more likely in the region 2-5).

There is a very economical way to figure out this: test the majority of the US population. Sure, the government will have to spend a few billion dollars, but that would possibly save a few trillion dollars in GDP losses. The fact that people and businesses are not requiring this right now from the government makes my head explode!

Yeah, claiming an IFR of 0.1% is laughable; it would mean everyone in NYC has been infected twice over.

Half of Iceland's population lives in the Reykjavik area. The rest are thinly spread out over the country - which of which is still inaccessible due to ice (usually until April/May). Comparing this to a densely populated South Korea is incredibly difficult.

Also, different genetics, different climate, different culture, different population density, different connectedness to China, and a 2 orders of magnitude difference in population size. As a rule of thumb, whenever you want to compare Iceland to another country, you probably shouldn't.

The comparison between the two countries is so difficult. The population of Iceland is around 360K, while South Korea is over 51 million (~140x). The population density is in the same order, 3 per Km^2 to 500 per Km^2 respectively (~160x).

South Korea cases peaked 45 days ago, Iceland peaked 2 weeks ago so their CFR are not directly comparable. Compare Iceland with a South Korea at a similar point post peak infections and the CFR look similar. https://en.wikipedia.org/wiki/2020_coronavirus_pandemic_in_S... https://en.wikipedia.org/wiki/2020_coronavirus_pandemic_in_I...

South Korea had 5 deaths per day on both 2/29 and 4/13 that’s a horrible sign.

I'm extrapolating from hospitalization rates for that reason. Otherwise, you'd get a 0.45% CFR in Iceland.

Looking at the raw data, I don't think Korea ever had below 3% using deaths/recoveries. Iceland is at 0.75% right now. Two weeks after peak, Korea was at a crude CFR (deaths/total confirmed) at 1.1%

With a sample size of 8 deaths, 0.45% is easily comparable to 1.1%. We are talking different infected populations, different healthcare systems, and so forth it’s expected to see that kind of a range. The US had what ~19 deaths out a single nursing home.

Also, deaths/recoveries is the least useful metric to compare countries as people with minimal symptoms recover first, again look at the South Korea or China graphs of the number of infected over time.

But you just ignored the evidence from the diamond princess?

and meanwhile germany's data points toward a similar conclusion as the south korean data

singapore also has a 1.5% deaths/recovered... and it's been higher in the past if you've been following closely (as high as 2%... question is where have all the new cases been coming from?)

icelands data could easily be skewed if they avoided a nursing home getting infected, given their low number of cases, and even there 1% fatality seems plausible.

An average age of 59 on the Diamond Princess (1.8% CFR) is not representative of the general population. This is a substantially more at-risk group.

Germany and Singapore are also missing many infections. A recent serological study in Germany actually argued for 0.4%.

You are correct that IFR is skewed by who the population is and what interventions are done. But then again, so is the often cited flu benchmark (where we have targeted vaccinations of at-risk groups).

(And age is a huge thing to be aware of skewing the data. e.g. the pediatric IFR from covid is on the order of seasonal flu)

https://www.reddit.com/r/medicine/comments/fyf0yh/megathread... you mean this serological study?

And taiwan is at 1.5% CFR as well?

And still 60 or so unresolved diamond princess cases with ~7 in critical condition?

Yes, I agree it is preliminary and not too much should be drawn off it.

Every country is missing large numbers of cases, so CFR doesn't mean much - randomized testing is what is needed.

Imperial College's paper (linked above which gives a 0.7% population IFR) uses Diamond Princess as an input. The relative risk ratio they give for someone age 70 (mean age on Diamond Princess) is something like 4.5x (IFR ~3%), so you'd natively guess about 80 deaths from the 2,666 passengers.

69 is the mean age of the passengers, the crew was like less than or equal 39 (about 2/3 passengers 1/3 crew I think)

hence why I divided by the passenger, not total, count

whoops, sorry it's 567 infections in passengers with 13 deaths. 2.3% CFR. Expected IFR 3% from Imperial College (17)

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