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Comment by scott_s | Hacker News Reader

A comment by Bradley Kuszmaul on that blog post gives a good reason why the scenario presented is not likely:

> Given the amount of testing being done in South Korea, we can rule out that there are a lot more people currently infected than we know about. And if there were a lot more people recovered than we know about, we would have seen deaths earlier in South Korea, since South Korea started their testing earlier. I suspect there's a lot more evidence that rules out the "fast and stealthy" hypothesis.

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It's possible (likely imho) that there is some missing factor that we have yet to discover that explains the funky nature of the data. Something about the people rather than a property of the disease. Almost like an allergy: peanuts are quite fine for everyone to eat, except those with severe peanut allergies.

What we do know is that it can't be quite "there were zillions of people infected so when we talk about 1% IFR really it's 0.01% so everything is fine", because there are accumulating bodies in various localized places around the world. There's nothing we know to say that pattern wouldn't repeated everywhere.

The type of testing S Korea does require the Virus to be present in the body and only work in a certain window of time. Once a Serological survey is done, we’ll know the true extant.

South Korea is far from the only place COVID-19 is present, and most of the rest of the world tests barely anyone, even if they have symptoms and would like a test, either due to lack of resources or formal policies of only testing hospitalised cases. I can detect my infection, but statistics on the rate it is spreading in the UK can't.

It's also pretty well established that even in symptomatic cases where testing is widespread the disease has a multi-day incubation period.

If the people who recover after mild/minimal symptoms do so within <5days (hypothetically), but people who have severe cases take 10 days to get severe, wouldn't that account for "would have seen deaths earlier in South Korea"?

Yes, that would. But what evidence do we have for that? I believe you're engaging in special pleading: appealing to an exception because it fits your conclusion.

Given the amount of testing being done in South Korea, we can rule out that there are a lot more people currently infected than we know about

That's a very strong claim. SK has done a lot of testing relative to most places but it's still:

a) A tiny amount relative to the population

b) Not a random sample of the population

Their tests were done at testing clinics that people had to take themselves to, which in many cases had large queues and generally you'd only go there if you actually felt really sick because otherwise why would you expose yourself to lots of probably really sick and infectious people?

So far there's overwhelming evidence that either a lot of people have the disease without symptoms, or the tests have a very high FP rate. There's also a lot of people writing like the person above, who are sure they've had the disease based on symptoms but were never tested. South Korea wasn't deploying their tests on people who were asymptomatic, they are doing the same as everyone else: testing people who present for testing or who otherwise seem to need it.

China tested hundreds of thousands of people in provinces with known cases, and found very little evidence of asymptomatic circulation. See my comment from a week ago, https://news.ycombinator.com/item?id=22475853, which quotes Bruce Aylward, an assistance director general and epidemiologist for the WHO.

Our current evidence points to there not being millions of asymptomatic people.

I see your HN comment from 2 weeks ago and raise you with a point in this article lifted from a recent Science paper. Namely, ...individuals with undetected infections were so prevalent in China that they apparently were the infection source for 86 percent of confirmed cases.

This is strong evidence of asymptomatic circulation.

This conclusion is not in contradiction to the evidence behind your previous comment. In mid-February with ~60k confirmed cases that would be 300-600k asymptomatic ones. Which means that China did not have millions of asymptomatic people at the time. And so it is no surprise that a broad testing regime failed to find what did not exist at that time.

However what it also means is that as the number of confirmed cases skyrockets, it WILL be true (and possibly already is) that the number of asymptomatic cases will be in the millions.

The study is on the initial outbreak in Wuhan when testing was in short supply.

And has the testing story improved relative to the need?

Also from the article and the same Science paper, For every confirmed case of COVID-19, there are likely another five to 10 people with undetected infections.

They were talking about abysmal testing rate:

https://science.sciencemag.org/content/early/2020/03/13/scie...

”We estimate 86% of all infections were undocumented (95% CI: [82%–90%]) prior to 23 January 2020 travel restrictions.”

“I’ll see … and raise” is known as a string raise and is seen as bad form or even cheating. Actions in poker must be atomic.

https://upswingpoker.com/angle-shooting-string-bet-raise/

Sorry, I don't know anything about poker, but didn't Riker do this all the time on TNG?

He did, and the poker on the show was generally abysmal. But partly for the ‘I’ll see you... and raise you’ prevalence in drama is that it creates a more dramatic situation. The dramatic effect is the very thing that can be taken advantage of in poker, and is why there’s a rule at most professionally run tables that what you claim, on your turn, is what you must do. Once you call, you can no longer raise no matter how much you want to.

Though the bigger reason for not allowing it, is that it can really add confusion and slow down the game when a person says call and the next person now has to wait until they’re sure the current asshole isn’t going to say ‘and raise’ before they can act.

Oh, and keep in mind that poker is full of assholes who will do all kinds of anti social behavior to gain an edge. So the fact that this is a standard rule really gives some idea as to just how annoying it is to the poker community.

I will keep that in mind if we ever play poker.

But the phrase remains a common idiom. And in an internet discussion like this, the rationale that makes it bad form in poker does not apply. I cannot see anyone's reactions until after my action is complete and I hit "reply". And therefore I cannot gain a read and final decision based on my incomplete first stage of the action.

What is the detection limit threshold on that test?

I haven't been able to make heads nor tales of his logic. In Guangdong province, at the peak of the outbreak, 0.47% of people tested were positive. Guangdong province has a population of about 110 million people. If that was a representative random sample, that would mean a lot of infections, so he's clearly relying on the fact that it's a sample of people who saw a doctor because they had symptoms. Except that I don't see how you can use that to say anything about asymptomatic cases. It just doesn't make sense.

It's 0.5% of people who were tested for the flu, not the general public.

That still does not rule out mild cases which are regarded as a regular viral illness.

SK is the exception.

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