Japan confirms coronavirus infections without symptoms | Hacker News Reader

Japan confirms coronavirus infections without symptoms

www3.nhk.or.jp

64 pointsreddotX82 comments

Missing "[of Coronavirus]". Yeah the guideline doesn't say it, and we probably can assume what infection they're talking about, but..

Reports say the German man who got the virus after having a business meeting with a Chinese visitor said he had a mild fever in the weekend and slept it off, and came to work on Monday, which must mean he had recovered. Reading that makes me think the virus isn't a death sentence like many are worried it is.

I am a bit more worried. There is a recent study that shows a mortality rate of diagnosed patients at 11% [1]. This is not the true case fatality rate, but a sample of patients seen in Wuhan hospital. The true percentage is probably lower due to bias.

We simply cannot calculate #fatalities / #cases, for a multitude of reasons. One, there is lag due to the clinical journey of the patients. Since both numbers rise exponentially, we really have to take that into account. Secondly, both numbers are most likely under-reported. In Wuhan, patients might not receive any treatment and might not be admitted to the hospital at all.

The short answer is: currently there is not enough information on the true mortality rate.

[1] Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

I'm too lazy to find the link but I've read the mortality rate is 3% - vs. 1% for a normal influenza infection. Obviously the information situation is really bad.

If it's really 11% that would be kind of worrisome. If it's just 3%, it's important to take care but in any case there's no point in panicking. The Chinese government indeed does well by building a new hospital complex so fast but the information politics is horrible. Also locking down a whole metropole region makes no sense. It's a signal to panic and people who are just a little sick might have a harder time to recover due to food shortage.

I'm sure, when this is over, the government will face some serious criticism, maybe this would even fuel protests on mainland China.

I don't think 11% is that worrisome. These are the cases where patients are ill enough to be admitted to the hospital. In the US, admitted patients of the flu have a 10% mortality rate, which is equivalent. We still don't have enough information regarding the virus but my guess is that its way overblown in the media.

Good point, also one needs to consider that is has been confirmed that there are people which got infected but practically showed no symptoms. That seems to be the case for the people that got infected in Germany.

> the German man [...] said he had a mild fever in the weekend and slept it off, and came to work on Monday, which must mean he had recovered.

Unfortunately, this isn't a valid assumption. Lots of people come in to work sick - just yesterday we had to ask our boss to send someone home because they showed up to work caughing and sneezing all day (Today, two other coworkers aren't coming in because they're not feeling well...)

But reports at sueddeutsche.de say that the (by now) 4 individuals in isolation are feeling very well, and are not showing any symptoms.

I also don't think the virus is a death sentence. I haven't done sufficient research to strongly support this opinion, but from what I've read across news articles is that most fatal cases were individuals with certain pre-conditions. That doesn't mean there's nothing to worry, but this isn't humanities downfall.

Also, just today there are reports [1] they released a 78 year old with both diabetes and hypertension - two of the six risk factors named so far - after he tested positive for nCoV-2019, went into critical condition, and fully recovered & tested negative.

Even for the elderly who have serious complicating health conditions, it's probably not a death sentence (unless you are immunocompromised). It's just a problem given how transmissible and sneaky this virus is.

[1] http://society.people.com.cn/n1/2020/0130/c1008-31564652.htm...

Less transmissible than flu, somewhat more deadly. But press needs sensational headlines...

I would turn that around. There is a substantial amount of healthy individuals who end up in in ICU or worse due to the virus. This is certainly different from the common flu, for example.

I may be misunderstanding you, but in case I was misunderstood: I didn't mean to say that the virus is harmless. It may have longer-term effects, and just because it is more deadly when certain conditions are met, we shouldn't just throw people who meet these conditions under the bus, or assume it's going to be harmless in other cases - it isn't.

But it's hard work not to fall for the paranoia that is fed (partly as side-effect) by the current attention-seeking headline-business formerly known as news.

According to Wikipedia, the flu causes 3-5 million severe cases and 650,000 deaths worldwide each year. https://en.wikipedia.org/wiki/Influenza

Yes, but the mortality rate of the common flu is much, much lower. Mortality of admitted patients is around 11% according to latest Lancet article.

Mortality of admitted patients of influenza in the U.S. is ~9% (https://www.cdc.gov/flu/about/burden/index.html). That's not that much different, and the U.S. has a lower mortality rate than much of the world.

The key here is “admitted.” Reports from Wuhan all indicate the hospitality rate is much much lower than usual circumstances since the patient count is over the roof (due to CCP trying to cover up initial cases), and a lot of patients don’t get treatments at all as a result. The high mortality rate is expected sunce only the most acute cases are admitted.

The flu kills hundreds of thousands of people each year. So far, this virus has killed maybe 200, out of 7,000ish infections.

We’re a long way away from knowing how dangerous this virus is, but the media hype is waaaaay ahead of reality.

The flu has a mortality rate of something like 0.1%, 200 our of 7000 is already 3%, 30x as deadly. Of course these aren't final numbers but the flu infects and afflicts vastly many more people than it kills.

Those 7000 infections are 7000 confirmed infections. Actual infections are going to be way higher than this (and hence, the mortality rate is going to be way lower) because of what was being discussed up-thread and in the article, i.e. infected people showing only minor symptoms and never getting admitted into a hospital where they would be tested for nCoV-2019.

> Unfortunately, this isn't a valid assumption. Lots of people come in to work sick

In the context of the virus, to me it feels that means the virus isn't a killer, so he got a fever that he had to sleep in the weekend, but he still managed to show up to work on Monday, presumably because he felt better.

And it's Germany, where there's no notion of "We're only allocating you X sick days a year, if you're sick more than that you don't get paid."...

It was established pretty early that mortality is quite low (3-10X lower than SARS?), however it also seems to be transmitted more easily.

I don't want to alarm anyone but the WHO posted to Twitter that while there are 100 or so deaths, there are 700ish in critical condition. The final numbers aren't even in yet. That'd be a 20% serious hospitalization proportion, but I'm not sure if that's the right way to make such a calculation - you may need to adjust the probability based on total uninfected population or something Bayesian like.

Edit: it was not the WHO official but an official looking WHO subsidiary. I'm trying to find the tweet.

China CDC official numbers are 170 dead and 1370 critical among 7711, as of 30th 00:00.

I imagine China is severely underreporting the numbers. I got downvoted last time I suggested it, but this is a modern day, protectionist, authoritarian state which controls what its people can say and see.

I don't know what particular phrasing you got downvoted for, but if it's along the lines of "China is authoritarian, therefore underreporting", that's a a non-sequitur and I can see why it would get downvoted.

What is true is that authoritarian regimes regularly use misreporting when it's in their own interest. If you want to make a solid argument, you need to explain why it is in the Chinese government's interest to underreport infection numbers.

For example, I could even imagine it being in their interest to overreport the mortality rate so they can afterwards boast about how effective their measures were in containing such a powerful and deadly disease. I don't say that's what happened, but it's within the realm of the imaginable.

They officially reported 144 influenza deaths in 2018, out of 700,000 infected. Would you prefer it if we said, "They use dramatically different statistical methods?" Lies, damned lies, and statistics, etc... Why? God only knows.

I would prefer if such evidence had been included in the initial post to make for a full argument.

It isn't just the fact that it is authoritarian, it's the combination of authoritarianism, protectionism, and an evident practice of lying to its own population in order to force narratives. Sure some of this applies to the U.S., but we don't have social credit scores or unmentionable events like Tiananmen.

I imagine one strong motivation could be that the CCP is trying to delay or prevent quarantine on the global stage, which would cripple the Chinese export based economy. Could be justified with the assumption that although numbers are worse, China expects it will nonetheless successfully contain the outbreak before other nations need to shut down flights and such.

Governments lie all the time. Communist style dictatorships like China and North Korea are particularly guilty, as their authoritarian rule depends on misinformation - not to mention in decades past, underreporting of negative data was not unheard of, for example in harvests of food when regions were in famine.

We have nothing to go on but China's word for these figures and their entire government is predicated upon varying degrees of misinformation. Any data which could possibly paint China in a negative light should be scrutinized.

They have already been reporting for some time that the estimate of this virus is 20-25% severe cases and about 3% fatality rate.

The number of severe cases is significant because that's initially what causes hospitals to be overwhelmed, not least because they'll obviously also want to isolate those patients from others.

Isn't the mortality low but the need for hospitalisation very high (10% maybe)? That's fine if you have 1000 people infected because you can free up (say) 100 hospital beds and save those 100 people. But if 1m people get it in your city, you won't be able to get 100k hospital beds from nowhere. So then a chunk of those people will die, even if only for want of an IV drip and some tlc.

If an infectious disease kills 1% of infected people it is likely to kill more people in total than one that kills 100% (unless a ubiquitous animal reservoir exists).

It's only a 3%(-ish) chance of dying going by numbers published so far.

That's much higher than a regular flu though.

The numbers published so far are probably biased to the high side because only serious cases seek treatment.

But it spreads much faster... 3% of a billion people infected is quite a lot.

Otherwise most reports cite that the dead were people who were already on their "deathbeds", and would (probably) die from a normal flu + complications (eg. pneumonia) anyways... but there are a few cases of younger people who died, that wouldn't if this was a "normal" flu.

Also depends on which demographic has been infected so there's of course some general bias as we don't have an even distribution across all age groups, sexes and profession, level of activity and and and ...

For example, if predominantly senior humans have been infected, the statistics may be skewed towards that group and you won't be able to make flat statements about younger people getting the virus.

I also still think that we don't really have solid numbers on the virus due to:

- unconfirmed sample characterization - likely false data spread on behalf of the Chinese government in order to save face/contain panic

It's ~20% "severe" plus fatal, per China CDC. Since many people who would end up dead is currently not dead, in-progress fatality rate is not very informative.

How do you get to that number?

I'm just dividing the number of (known) deaths by the number of known infections.

As other's have pointed out this isn't the most reliable way of doing it, but it gives some indication.

No, it does not give any information for a multitude of reasons.

1. Deaths are lagged by known cases

2. Both are skewed distributions

3. These people might have received professional care when it was available. During an outbreak, the available health care will decline.

Those just mean the estimate is inaccurate. When dealing with something entirely unknown almost any estimate is better than nothing.

Sure it could end up being off by a factor 10 either way, but even then it's still informative.

Estimations work when dealing with symmetrical distributions. You might be wrong either way. But these distributions are fundamentally not symmetrical! Also, you should compare deaths with number of cases a couple of days ago (like 7), since that’s the time between diagnosis and death.

The distributions are asymmetrical in exactly the way that argues against your fear-mongering across this thread: only the most serious cases are self-selecting for treatment and testing.

The infection rate is, in all likelihood, much higher than these early numbers suggest. People don’t go to the hospital for sniffles, and therefore, the bulk of infections don’t show up. Deaths almost always get counted.

How do you figure that? Going off this source I see 170 deaths and 133 recovered. So of those 303 that have been infected with it, 170 have died which is 56%. You can't count the other 7783 that are currently infected since we haven't seen their outcome yet.

https://gisanddata.maps.arcgis.com/apps/opsdashboard/index.h...

This is not the right way of counting it. If it takes 40 days to be declared fully recovered, the recovered number is going to stay low at least 40 days (even though the people on their way to full recovery will most likely survive), while the death number will be increasing from the pool of people which became infected later.

To count it properly you need to follow what happened to people infected at the same date.

Interesting, that makes sense!

The estimate requires some extrapolation based on other epidemics. Dying from it isn't going to take as long as recovering so you should expect a particularly large skew this early. But more generally you'd expect more mild cases to go underreported, be a lower priority for testing (which seems to be the bottleneck for reporting cases in some areas), etc.

It's probably more dangerous for older and younger people. So whilst many will be ok, due to its rapid contagion even if it is only a death rate of 0.01% that could be a lot of people.

You can't extrapolate from a single individual.

This coronavirus is said to be very similar with SARS from 2002-2003, which had a mortality rate of 11%.

I see a lot of people discussing the fatality rate, and trying to lower the importance of being infected based on that.

We should keep in mind that "surviving" the virus does not mean you will live happily ever after.

A lot of SARS patients that "recovered" ended up with lung or kidney disease afterward.

People are looking at the fatality rate as a % of total infected, which is a misleading statistic. A better metric would be fatality : recovery rate.

That is also misleading.

The article says a "new type of coronavirus", which is presumably a misunderstanding on the reporter's part; it seems more likely that these are asymptomatic carriers of the same virus.

However, if there really is a symptomless or near-symptomless variant, this would actually be great news, since it would spread rapidly and provide immunity against virulent strains. And this in fact is what appeared to happen with the Spanish flu, where natural selection tended to prefer less virulent strains. (Really sick people stay home/hospitalized and don't spread the virus; less sick or asymptomatic carriers move around and spread it.)

"New type of coronavirus" is is the current official name for the coronavirus spreading from Wuhan.

That's not the way I read the report. I read it as it is confirmed that the virus can spread before the symptoms appear. No where is it stated that there is a new variant.

I'm not sure that et even says that, just that they tested everybody who arrived on the plane and found a few with the infection but no symptoms. It doesn't say whether they can spread the infection in that state.

Yes you are right. I misread.

> The article says a "new type of coronavirus", which is presumably a misunderstanding on the reporter's part

It's ambiguous, but I think they just mean 2019-nCoV. It's the one that was discovered late 2019. As opposed to the coronaviruses that were already known for years or decades.

Haven't the genetic sequences shown that there's so far only one variant? It's not surprising that there would be symptomless carriers, since it apparently can have quite a long incubation period. They may develop symptoms within a couple of weeks.

Yes. Sequences strongly support single zoonotic introduction.

In some ways that's positive. If the number of cases is higher than thought, then the deadliness is lower.

That depends. They just may not be showing symptoms yet. If that's the case then these are lagging indicators of what's to come. There could be thousands that have the virus and won't start to show it for another few days. And those would have been interacting with others that could catch it and might not show it for a week or so.

75% of those cases are less than 5 days old, 50% are less than 2-3 days. Assuming it takes a day or two for symptoms to ramp up, the death count so far is half or less of what it will be for the 7.7 now infected. Just from these numbers, I'd expect it to end up around 4.5%.

That brings up the question of how many cases there really are? How many people have been infected without any symptoms already?

Quote: "Two passengers refused to take the test. And health officials say they will continue to persuade them to get tested.".

Wait, what? wtf is that even possible with a government chartered flight? And then what, the 2 were just left to go home and officials come to them every day "hey, wanna get tested today?"

I wonder what the specificity of the test is. Even 99% would still mean that out of 200 passengers, these two would just be the expected number of false positives, unless they have done a confirmatory test on them.

They are professionals. Let's give them benefit of doubt, shall we? (I don't know about this specific case, but yes confirmatory testing is usual protocol.)

Is testing fast now? Do patients who don't have symptoms spread it effectively?

I'm not an expert, but I see two main possibilities: It can be contained. Or it will spread all around the world and only vaccines will later make it go away, if a large enough percentage of the population is vaccinated. How long does it take to create a vaccine nowadays? And mass production...

Here's a Twitter thread from an expert with thoughts on what we'll need to do if it's not contained: https://twitter.com/t_inglesby/status/1221434570714669056

It’s so infuriating to try to read that great info in a million disjointed tweets. I don’t get Twitter character limits at all in the year 2020.

Probably it's just the wrong tool for this job.

It's so infuriating to see people using Twitter for what it's not, and also in this case for causing undue worry.

I hate people using it as a freaking Powerpoint replacement... Bullet point after tedious bullet point, great job presenting your knowledge, Mr. Expert! /s

It's indeed sad, but apparently many people think "if it's good enough for the POTUS, it's good enough for me!"

It's heartening to see the way that we're reacting to this threat.

We need to be doing exactly the same thing in the fight against climate change.

> How long does it take to create a vaccine nowadays?

https://www.scmp.com/news/hong-kong/health-environment/artic...

From this article: “If the vaccine appears effective and safe in a number of animal species, it will go into clinical trials on humans. This takes at least one year even if expedited,” Yuen said.

Inovio of San Diego already have a computer designed but untested DNA vaccine. In the past DNA vaccines have not been approved for use in humans but they are partnered with a Chinese company and I'm not sure the Chinese will be as conservative as the FDA in terms of trying things. [pasted from another thread]

Their previous Elboa vaccine seemed to work well in tests though I think it never made it to the field. http://ir.inovio.com/news-and-media/news/press-release-detai...

I sometime think the testing protocols are a bit over cautious when you have a candidate that is probably safe and quite likely effective.

Even fast-tracked development will take 1-2 years.

Edit: sorry, I basically repeated what the comment above said. Somehow I overlooked that...

Is that including production? Or just getting approval?

The virus changes rapidly, not unlike the flu. A vaccine isn't likely to be effective to eradicate it, and it will likely stay around as a permanent epidemic like the flu or HIV. Virulence can increase or decrease randomly in the future, but the spread doesn't seem like it can be contained, since a perfect quarantine can't be maintained at this scale. We'll have to live with a new virus and pay the price of some natural selection.

Does immunity still hold for the changed virus?

Depends whether the targeted antigen has changed. Best case (for humans) is if it couldn't escape the targeting without deactivating the virus.

RNA viruses do change quickly, but influenza's probably on a different level with its multi-segment, randomly assorted genome.

Polio also changes rapidly (it's faster than HIV), but we are nearing polio eradication with vaccine. Relationship between vaccine and mutation is complex.

I didn't know it changed, let alone that fast. Really makes it all the more impressive.

This is the first thing that came into my mind when I read that various governments wanted to evacuate their nationals from Wuhan. THAT IS HOW YOU HELP THE VIRUS TO SPREAD, DUMMIES!

I get that they want their citizens to be safe (genuinely, or to win political points at home - it does not matter), but it goes directly against best practices in disease control.

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