Coronavirus: South Korea’s aggressive testing gives clues to true fatality rate(scmp.com)
scmp.com
Coronavirus: South Korea’s aggressive testing gives clues to true fatality rate
https://www.scmp.com/week-asia/health-environment/article/3065187/coronavirus-south-koreas-aggressive-testing-gives
67 comments
The article's 0.6 mortality rate seems to have been obtained by dividing the number of confirmed infections (6284) by the number of deaths so far (40) - source: https://www.arcgis.com/apps/opsdashboard/index.html#/bda7594...
This is completely misleading, unless the other 6244 people have already recovered.
The low death rate so far is because the detected illnesses have not yet run their course.
Edit: The source above says that the number of people in South Korea who have recovered from the illness is... 135.
This is completely misleading, unless the other 6244 people have already recovered.
The low death rate so far is because the detected illnesses have not yet run their course.
Edit: The source above says that the number of people in South Korea who have recovered from the illness is... 135.
Rumors of a few young people discharged after they have recovered and testing negative have later died with the virus coming back. I agree we have too many stories with even stories of 2 different strains one being deadlier than the other and people being infected by both at the same time. Actual mortality rate we will find out after 1-2 years only even that only if they have a test where can check if a healthy person ever contracted the infection in the past then test a few thousand people randomly. Btw China numbers show that people either survived or died in the third or fourth week after their symptoms got worse in 14-20 days after infection. So Korean mortality rate might even go up as it is still too early to tell .
Don’t spread “rumors”.
Isn't it that there are two main strains, one (30% of cases) is less lethal (and this one is predominant in South Korea) and the other (70% cases) is e.g. in Italy?
Two strains source: https://www.newscientist.com/article/2236544-coronavirus-are...
Two strains source: https://www.newscientist.com/article/2236544-coronavirus-are...
Based on the top response here: https://news.ycombinator.com/item?id=22499569
There are more than 100 strains, which you can see here: https://nextstrain.org/ncov
There are more than 100 strains, which you can see here: https://nextstrain.org/ncov
The two strains paper seems to be hot air:
http://virological.org/t/response-to-on-the-origin-and-conti...
http://virological.org/t/response-to-on-the-origin-and-conti...
What speaks against this theory is that in austria, which is north of italy, the cases so far have been pretty mild.
Those infections are still recent. The virus takes weeks to kill you.
I was watching a conference, they were saying the cruise ship was the best data, because everybody got exposed, tested and had a follow-up.
They were old on average though and all got relatively good treatment (not too many overcrowded hospitals). Something that data makes very clear is that there are many asymptomatic cases though - around 50% of the people who tested positive did not experience any symptoms. Which suggests that areas where only people exhibiting symptoms get tested are probably missing a large proportion of carriers.
The cruise ship has a massive age bias. Most passengers were 60+
that's the difference between "best" and "perfect"
Seems like an easy variable to adjust for.
The cruise ship also didn’t had proper medical facilities.
This is somewhat the problem with these epidemics the mortality rate is highly dependent on the available level of care.
If the healthcare services get overwhelmed the mortality rate can easily spike.
This is somewhat the problem with these epidemics the mortality rate is highly dependent on the available level of care.
If the healthcare services get overwhelmed the mortality rate can easily spike.
Does anyone know of any good, publicly accessible case data (for any country)?
E.g. for each case,
E.g. for each case,
date of detection, age of patient, ongoing|recovery date|date of deathTry This page from Hokkaido government in Japan. You should be able to extract relevant data from the table and pdf using a translator.
http://www.pref.hokkaido.lg.jp/hf/kth/kak/hasseijoukyou.htm
Table shows quite a bit of data about each case including age, gender, location, any link discovered to other patients and status. The pdf shows additional data on when they had fever and other symptoms, when they went to different medical facilities and when they were confirmed as infected.
http://www.pref.hokkaido.lg.jp/hf/kth/kak/hasseijoukyou.htm
Table shows quite a bit of data about each case including age, gender, location, any link discovered to other patients and status. The pdf shows additional data on when they had fever and other symptoms, when they went to different medical facilities and when they were confirmed as infected.
The best and closest to what you’re looking for comes from Johns Hopkins:
- https://data.humdata.org/dataset/novel-coronavirus-2019-ncov...
The GitHub repo with datasets:
- https://github.com/CSSEGISandData/COVID-19
Start there, and reach out to the staff if you’re looking for something more specific. They may be able to point you in the right direction.
- https://data.humdata.org/dataset/novel-coronavirus-2019-ncov...
The GitHub repo with datasets:
- https://github.com/CSSEGISandData/COVID-19
Start there, and reach out to the staff if you’re looking for something more specific. They may be able to point you in the right direction.
Yeah, I'm aware of the JHU dataset. Unfortunately working out useful CFRs from that is not easy.
You need to be able to figure out infected_at_t_and_dead/(infected_at_t_and_recovered+infected_at_t_and_dead) for some time t sufficiently in the past so that basically everyone falls into these two categories.
And if you want to draw transferable conclusions you also need an interval where treatment conditions were relatively uniform (e.g. already completely overwhelmed health system, or health system that could cope, throughout). As well as an age breakdown of recovered and dead.
The data from Italy does not look promising, they have an old population but seem to have reacted well and still have capacity to treat people. And yet CFR seems 3.8%, without excluding people who are ongoing and will die in the next days and weeks.
It would be very interesting to have a more detailed comparison with the South Korean outbreak, where again reaction has been very good as well and we could look at a subset of people for whom we have no undetected cases, so very good estimates ought to be possible.
You need to be able to figure out infected_at_t_and_dead/(infected_at_t_and_recovered+infected_at_t_and_dead) for some time t sufficiently in the past so that basically everyone falls into these two categories.
And if you want to draw transferable conclusions you also need an interval where treatment conditions were relatively uniform (e.g. already completely overwhelmed health system, or health system that could cope, throughout). As well as an age breakdown of recovered and dead.
The data from Italy does not look promising, they have an old population but seem to have reacted well and still have capacity to treat people. And yet CFR seems 3.8%, without excluding people who are ongoing and will die in the next days and weeks.
It would be very interesting to have a more detailed comparison with the South Korean outbreak, where again reaction has been very good as well and we could look at a subset of people for whom we have no undetected cases, so very good estimates ought to be possible.
This kind of data is called a "line list".
There's two good ones from Harvard and University of Washington "BeOutbreakPrepared" linked on https://nssac.github.io/covid-19/covid-19_imported_cases/
Thanks a lot for teaching me the right term and linking this data set!
There is some good data on 1100 early cases in China. See https://www.nejm.org/doi/full/10.1056/NEJMoa2002032
Thanks! The ratio of CT abnormalities and proportion of severe cases in young-ish patients in that one is scary. 40% of people in 14-49 age bracket were classed as severe cases.
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Sweden, for e.g.: https://www.thelocal.se/20200304/who-are-the-coronavirus-pat...
This corroborates Chinese numbers. China has also been very aggressively testing and mortality outside Wuhan is no more than 1% (according to Dr Aylward, following the WHO fact finding mission to China).
This implies very serious efforts, though, which I'm not sure we're seeing in the West.
This implies very serious efforts, though, which I'm not sure we're seeing in the West.
Yes the WHO report is very clear : mortality in Wuhan is 6% because they were overwhelmed by the number of cases.
The lack of decisiveness in the west worries me. It's like they wait for the hospitals to be full before they decide quarantine might be in order.
The lack of decisiveness in the west worries me. It's like they wait for the hospitals to be full before they decide quarantine might be in order.
> The lack of decisiveness in the west worries me.
From a cynical point of view, the governments in the west might see this disease as a god-send. It mostly kills the old and sick. So if you let it run its course through the whole population, the strain on pension and public health systems will (eventually) be reduced -- "sozialverträgliches Frühableben" as one German top medic once called it. A disease that mostly leaves the young and productive part of the population intact might thus be welcomed as a solution to the demographic problems in the west.
Note, I don't agree with this point of view, but it might help explain the timid response in the west.
From a cynical point of view, the governments in the west might see this disease as a god-send. It mostly kills the old and sick. So if you let it run its course through the whole population, the strain on pension and public health systems will (eventually) be reduced -- "sozialverträgliches Frühableben" as one German top medic once called it. A disease that mostly leaves the young and productive part of the population intact might thus be welcomed as a solution to the demographic problems in the west.
Note, I don't agree with this point of view, but it might help explain the timid response in the west.
This is good news for stocks in 2021.
People think it's harmless, which makes them not worry about it at all, which in turns makes it much more dangerous than it would be if we took basic decisions.
Everyone in my office could work from home, but we're not allowed because "it's not that bad" yet. One of my colleague is coughing for a week and still coming in and everyone is making joke about "aha he could be patient 0 here".
Everyone in my office could work from home, but we're not allowed because "it's not that bad" yet. One of my colleague is coughing for a week and still coming in and everyone is making joke about "aha he could be patient 0 here".
I can't speak for all western countries but in my country (France) if the government tried to impose quarantine on the same level as China, I'd expect riots.
People here aren't as docile as Chinese people and don't fear their government. If a city was quarantined like Wuhan with the situation turning to shit, many people would take to the street to protest instead of staying nicely confined at home.
And if the government's repression got too harsh there, you'd get protests all around the country in support.
That's why I haven't heard anything from my government about potential large-scale quarantine. They know that here it probably would make the situation worse.
People here aren't as docile as Chinese people and don't fear their government. If a city was quarantined like Wuhan with the situation turning to shit, many people would take to the street to protest instead of staying nicely confined at home.
And if the government's repression got too harsh there, you'd get protests all around the country in support.
That's why I haven't heard anything from my government about potential large-scale quarantine. They know that here it probably would make the situation worse.
1) martial law will deal with eventual riots.
2) i wouldn't be so sure that quarantine measures would be such universally disliked. it'll take a couple deaths and a few tv interviews with medical personnel with an overwhelmed hospital in the background to sway the public emotion in the containment direction. it better be executed well, though, or riots become a serious proposition.
2) i wouldn't be so sure that quarantine measures would be such universally disliked. it'll take a couple deaths and a few tv interviews with medical personnel with an overwhelmed hospital in the background to sway the public emotion in the containment direction. it better be executed well, though, or riots become a serious proposition.
This is France we're talking about. There's already been a recent series of riots where a number of people have suffered debilitating injuries from the heavy riot control tactics - 24 people lost eyes!
Where do you escalate from that? Machine-gunning people in the streets?
Where do you escalate from that? Machine-gunning people in the streets?
Ah yes the famous french protests just about anything they don't like on a given day. It would be supremely stupid and arrogant to go to mass protests when facing such quarantine due to deadly virus like this one, but I have no doubt that's exactly how it would unroll en France.
IMO, this virus isn't as deadly as that. It was reasonable for China to implement such measures because 1) at the time they didn't know how bad it was and 2) their people are actually quite compliant with what their government asks them.
But now, we know this virus isn't ebola's death rate combined with measle's R0. Large scale quarantine like in China is probably overkill and quite risky if your population isn't as docile as populations in authoritarians regimes.
Closing schools, cancelling mass events and asking people to work from home if they can is a more measured approach. Even without that, the apocalypse isn't coming anytime soon.
But now, we know this virus isn't ebola's death rate combined with measle's R0. Large scale quarantine like in China is probably overkill and quite risky if your population isn't as docile as populations in authoritarians regimes.
Closing schools, cancelling mass events and asking people to work from home if they can is a more measured approach. Even without that, the apocalypse isn't coming anytime soon.
> People here aren't as docile as Chinese people and don't fear their government
Don't underestimate the sense of doing what's good for the community and the patriotism of the Chinese people (and I'm sure many others).
I think they understood what was at stake and what had to be done, and did it but not because they are "docile" or because they "fear their government".
Don't underestimate the sense of doing what's good for the community and the patriotism of the Chinese people (and I'm sure many others).
I think they understood what was at stake and what had to be done, and did it but not because they are "docile" or because they "fear their government".
Yes, people here aren't that eager to make sacrifices for the greater good. Unless it's other people doing the sacrificing.
I hope by 'docile' you mean wise and responsible.
Yep. Early detection makes for better outcomes and smaller fatality rate.
How come, I thought there was no cure?
successful containment yields lower peak cases which means medical infrastructure can cope better. there's no cure but there are worthwhile treatments.
"containment" doesn't mean "early detection". You can yield better "containment" by issuing strong recommendation to work from home and maximize staying at home for two weeks or so.
um, i agree.
Good question. Since once someone is infected, how can early detection and being under quarantine help in recovery?
The answer is that with early detection, and keeping the virus numbers low, the health care network can be kept free for caring for the cases that do come through.
And ICU level care cannot cure the virus but can reduce fatalities.
The answer is that with early detection, and keeping the virus numbers low, the health care network can be kept free for caring for the cases that do come through.
And ICU level care cannot cure the virus but can reduce fatalities.
Early detection means up to 100x more people overloading hospitals, doesn't it? It's much better to just stop as much as possible for 2 weeks - work from home etc.
Early detection does two things:
1. Allows you to isolate the person before they spread it further.
2. Allows you to be ready to treat their pneumonia which increases their survival chances.
You said early detection leads to better outcomes - so point 1 doesn't apply. Treating pheumonia is last stage process, early detection does nothing to help help here as well.
It’s possible to contain a small outbreak, much more difficult to contain a large one. Think of it like a California brush fire:
- If someone is witness to the start of the fire, they’re going to call the fire department who will mobilize all resources available to a small area -> fire is contained quickly and with minimal loss of life or property
- If the fire starts in a remote area with nobody around for miles, it will get bigger and avoid detection until it becomes an imminent risk to people. At that point, the same resources will be spread across a larger area. As the wildfire grows, the wind caries embers and sparks other fires miles away, making the situation worse.
- If someone is witness to the start of the fire, they’re going to call the fire department who will mobilize all resources available to a small area -> fire is contained quickly and with minimal loss of life or property
- If the fire starts in a remote area with nobody around for miles, it will get bigger and avoid detection until it becomes an imminent risk to people. At that point, the same resources will be spread across a larger area. As the wildfire grows, the wind caries embers and sparks other fires miles away, making the situation worse.
The deaths tend to be from secondary effects, not covid-19 directly, i.e. the exacerbating pre-existing conditions such as lung problems or just being old or otherwise infirm. Early detection makes catching and managing those complications easier so the patient has a better chance of riding out covid-19 itself.
The SARS in SARS-CoV-2 stands for Severe Acute Respiratory Syndrome. It's the primary infection that kills, such as by directly causing pneumonia.[1] By contrast, seasonal influenza deaths are usually by secondary infections, mostly bacterial pneumonia. The H1N1 influenza strain was more like SARSr-CoV in that deaths were usually from primary viral pneumonia.[2]
Obviously if you suffer from preexisting health issues, especially cardiopulmonary issues, you're far more likely to develop pneumonia, primary or secondary, or otherwise succumb.
[1] This page equivocates Severe Acute Respiratory Syndrome with pneumonia: https://medlineplus.gov/ency/article/007192.htm
[2] https://www.sciencedirect.com/science/article/pii/S120197121...
Obviously if you suffer from preexisting health issues, especially cardiopulmonary issues, you're far more likely to develop pneumonia, primary or secondary, or otherwise succumb.
[1] This page equivocates Severe Acute Respiratory Syndrome with pneumonia: https://medlineplus.gov/ency/article/007192.htm
[2] https://www.sciencedirect.com/science/article/pii/S120197121...
There's no silver bullet "cure", but it turns out that ventilating people while their immune system deals with it allows a lot of people to recover.
What does it mean to "ventilate" a person?
Uh, just looked at map and Pyongyang/North Korea is holding great on stats - zero infections. Does anyone know if it's becase a) almost nobody travels there, or b) there's no outgoing information or both?
I've heard that their border with China is pretty porous and that people cross it on a daily basis to get contraband into the country.
So I'd say b) is most likely. People are criticizing China's release of information but compared to NK, they're pretty transparent.
Even if the situation on the ground was disastrous, I'd bet that the government would do everything to hide it.
So I'd say b) is most likely. People are criticizing China's release of information but compared to NK, they're pretty transparent.
Even if the situation on the ground was disastrous, I'd bet that the government would do everything to hide it.
I saw a couple of articles written in Korean - those stated, in North Korea, there are only limited people, in a novel class, are able to travel outside the country. Also, unbelievable point was, North Korean government executed one inspected person immediately after finding out.
Two people were executed. One for smuggling(The regime was figuring out how he had contracted the virus after NK barred Chinese people from entering the country and they found out that he was meeting Chinese smugglers), and the other for breaking quarantine and going to a public bath.
It is also c) they may not have testing kits or may not be using what WHO sent to various countries.
I'm guessing a combination of information blackout, and lack of testing equipment. Where are the world's PCR machines located?
It's a totalitarian country with total information control. There could be thousands dead and we'd have no way of knowing.
My theory on the coronavirus. I've managed to convince myself to have moderate levels of confidence in it; please tear it apart.
1) The Diamond Princess is our best source of data. Every person who got infected on it was identified (~700), and those who were infected got the best medical care possible. This led to a ~1% mortality rate (6/700) and a ~5% ventilator support rate (35/700). 6/700 is subject to significant error in both directions, but let's go with it.
2) Their average age was in the upper 40s, so assuming younger people don't suffer the most serious ill effects from it, a guess for the general population might be a 0.5% base mortality rate and 2.5% ventilator support. This is a rough order of magnitude estimate: obviously expected mortality should be adjusted for actual age distributions.
3) South Korea's mortality rate is 0.6%. Cases outside of Wuhan but within China have a reported mortality rate of 0.4%. Singapore (at ~100 cases) is 0%. These are all consistent with the estimated mortality rate I extrapolated from the DP.
4) All of the areas mentioned in 3) have very aggressive testing protocols. No evidence has come up suggesting widespread infection among the broader community. This includes China randomly sampling some areas and not finding meaningful unknown pockets of infection.
5) But what about Wuhan? It has a much higher mortality rate (>3%). The reports on the ground suggested that it was the medical system being overwhelmed that drove the mortality through the roof. If we assume everyone who needs a ventilator but doesn't get one dies, that explains in one fell swoop Wuhan's elevated mortality rate.
6) What about Italy? Its mortality rate is ~3.5%. But, compare the number of hospital beds in Italy and SK. It's ~3/1k vs ~10/1k. SK is already running into issues with hospital bed availability, so it stands to reason that the situation is much worse in Italy. Italy also has a significantly older population than SK. So it's starting to run into the same nightmare scenario as Wuhan. Of note, the US has a younger population than Italy, but fewer hospital beds.
7) What about Iran? It has ridiculous mortality rates. My best explanation is that testing constraints probably lead to more undercounting of infections in the hardest hit areas, so Hubei, Italy, and Iran probably all have artifically elevated mortalities, while the reality for all of them is much closer to 2.5%.
8) There's no need for weird hypotheses about Asians having different proteins in their lungs, there being multiple strains that act radically differently from each other, China running secret death camps for the infected, etc.
9) Policy-wise, we need to keep the rate of infection low enough such that the medical system is not overloaded. This is possible, as it's been done in multiple countries, and that's the difference between a severe-but-normal flu season and over a million dead in the USA. We also have to start taking decisive action yesterday, with today being a second best option.
1) The Diamond Princess is our best source of data. Every person who got infected on it was identified (~700), and those who were infected got the best medical care possible. This led to a ~1% mortality rate (6/700) and a ~5% ventilator support rate (35/700). 6/700 is subject to significant error in both directions, but let's go with it.
2) Their average age was in the upper 40s, so assuming younger people don't suffer the most serious ill effects from it, a guess for the general population might be a 0.5% base mortality rate and 2.5% ventilator support. This is a rough order of magnitude estimate: obviously expected mortality should be adjusted for actual age distributions.
3) South Korea's mortality rate is 0.6%. Cases outside of Wuhan but within China have a reported mortality rate of 0.4%. Singapore (at ~100 cases) is 0%. These are all consistent with the estimated mortality rate I extrapolated from the DP.
4) All of the areas mentioned in 3) have very aggressive testing protocols. No evidence has come up suggesting widespread infection among the broader community. This includes China randomly sampling some areas and not finding meaningful unknown pockets of infection.
5) But what about Wuhan? It has a much higher mortality rate (>3%). The reports on the ground suggested that it was the medical system being overwhelmed that drove the mortality through the roof. If we assume everyone who needs a ventilator but doesn't get one dies, that explains in one fell swoop Wuhan's elevated mortality rate.
6) What about Italy? Its mortality rate is ~3.5%. But, compare the number of hospital beds in Italy and SK. It's ~3/1k vs ~10/1k. SK is already running into issues with hospital bed availability, so it stands to reason that the situation is much worse in Italy. Italy also has a significantly older population than SK. So it's starting to run into the same nightmare scenario as Wuhan. Of note, the US has a younger population than Italy, but fewer hospital beds.
7) What about Iran? It has ridiculous mortality rates. My best explanation is that testing constraints probably lead to more undercounting of infections in the hardest hit areas, so Hubei, Italy, and Iran probably all have artifically elevated mortalities, while the reality for all of them is much closer to 2.5%.
8) There's no need for weird hypotheses about Asians having different proteins in their lungs, there being multiple strains that act radically differently from each other, China running secret death camps for the infected, etc.
9) Policy-wise, we need to keep the rate of infection low enough such that the medical system is not overloaded. This is possible, as it's been done in multiple countries, and that's the difference between a severe-but-normal flu season and over a million dead in the USA. We also have to start taking decisive action yesterday, with today being a second best option.
Something to keep in mind is that you can't properly calculate the mortality rate if the cases haven't "completed" yet. Yes, a certain number of people died from the Diamond Princess spread (I read it's more than 6 though - apparently some of the fatalities get their death counted with their country of origin rather than in the Diamond Princess stats). But there are still 34 or so people in very poor condition in hospitals, who might still die.
Some of the 392 asymptomatic cases out of 706 confirmed cases (55.5%) on the Diamond Princess may have developed symptoms at a later point after they have been released, but this was presumably a small minority as most develop symptoms sooner rather than later.
https://res.mdpi.com/d_attachment/jcm/jcm-09-00538/article_d...
Early case fatality rate estimates tend to be somewhat overestimates. Anecdotally, for 2009 H1N1 vs later estimates differed by a factor of 100.
https://www.reddit.com/r/COVID19/comments/f9jo57/historical_...
https://res.mdpi.com/d_attachment/jcm/jcm-09-00538/article_d...
Early case fatality rate estimates tend to be somewhat overestimates. Anecdotally, for 2009 H1N1 vs later estimates differed by a factor of 100.
https://www.reddit.com/r/COVID19/comments/f9jo57/historical_...
I think this is roughly accurate and agrees with what the experts at Twiv have been saying.
The next two questions are whether or not it can be contained without the economy-shutting down response we saw in China, and whether the upcoming warmer summer weather will sufficiently lessen community spread (at least in the Northern hemisphere) to allow for some meaningful containment.
...and then, of course, we're hoping for an effective vaccine by summer 2021.
The next two questions are whether or not it can be contained without the economy-shutting down response we saw in China, and whether the upcoming warmer summer weather will sufficiently lessen community spread (at least in the Northern hemisphere) to allow for some meaningful containment.
...and then, of course, we're hoping for an effective vaccine by summer 2021.
South Korea already has huge experience with SARS and MERS. Most other countries don't, so "true fatality rate" would be higher. The demographics(age distribution) is also different in other countries.
The response to MERS was a total shitshow (no laws against breaking quarantine, quarantined patients playing golf, flying to China, etc.) and we were lucky the virus didn't spread too easily. But they seem to have learned from that and are handling things really well this time: https://edition.cnn.com/2020/03/02/asia/coronavirus-drive-th...
Whatever the global mortality rate shakes out to be in the long-run, it’s impossible to ignore the fact that this virus killed nearly a dozen nursing home residents in the span of 2 weeks. There’s a lot we don’t understand about COVID-19, certainly more than a single metric can tell us.
Based on what we’re seeing in the state of Washington and around the world, it’s safe to say that older patients are at higher risk for developing respiratory failure. Beyond that, it’s simply way too early to draw conclusions.