7 ms·

Does this mean the mortality rate is, approximately, 10x less than currently estimated? (86% of cases unreported, eg about 1 in 10 reported, assume that number

by nmca 7y ago

Does this mean the mortality rate is, approximately, 10x less than currently estimated? (86% of cases unreported, eg about 1 in 10 reported, assume that number of unreported fatal cases is 0) Edit: closer reading suggests the optimism is sadly unwarranted, the headline under-reporting number of 86% is from the early pre-travel ban model, post-travel-ban estimates give a 65% detection rate, combined with the increased number of cases in this later period this implies that naive mortality estimates are more like 2x off than 10x off.

nmca 7y ago
I have been considering other ways to estimate this, and looked at numbers for Singapore, which I believe has particularly strict testing. They show a much lower mortality rate than the other estimates I have heard, but only at n=250. This may also be confounded by wealth/healthcare quality. Does anyone have a decent model of the mortality rate?
arcticbull 7y ago
Yeah so, what the data has been pointing to the whole time.
- cycrutchfield 7y ago
  Which data?
  - arcticbull 7y ago
    Well the cruise ship showed 55% of folks being asymptomatic and 80% of the remainder have mild flu like symptoms, and with an R0 of 2-3 for every person you do see get tested positive, there’s a mountain of folks spreading it without symptoms. This also explains why Korea’s [edit: case fatality] rate is so low and so correlated with their high incidence of testing. I wouldn’t be surprised if the majority of us have already had it. There’s a decent shot this all amounts to a big ol nothing burger.
    - bathtub365 7y ago
      Despite all experts saying it is actually a big problem? It's a disease that spreads rapidly and kills people who wouldn't otherwise have died. That doesn't sound like nothing to me.
      - arcticbull 7y ago
        It tends to work out better for those who overstate threat than those who understate, both in the moment (you get more attention) and after (if you’re right you get yet more attention, and if you were wrong everyone gives you a pass due to the mass collective panic).
    - cycrutchfield 7y ago
      Korea's mortality rate is about 1%, and that is primarily due to a relatively youthful population and the healthcare system not being saturated. I'll also note that 1% is still 10x deadlier than the flu. It sounds like you may be interested in reading this paper: https://www.medrxiv.org/content/10.1101/2020.03.04.20031104v1.full.pdf https://www.medrxiv.org/content/10.1101/2020.03.04.20031104v... >I wouldn’t be surprised if the majority of us have already had it. There’s a decent shot this all amounts to a big ol nothing burger. Unsupported by any evidence and complete wishful thinking. Please stop with the irresponsible speculation.
      - MikeAmelung 7y ago
        You don't know the difference between case fatality rate and mortality rate, so maybe you should stop with the irresponsible speculation.
        cycrutchfield 7y ago
        I was just using the language of the person I was replying to. Would you like to be more pedantic?
        7y ago
nerdface 7y ago
What I wonder is, does this mean deaths are also under reported because they're being attributed to the flu or pneumonia without adequate testing?
- learc83 7y ago
  A few maybe, but there haven't been large numbers of additional pneumonia deaths beyond those attributed to coronavirus.
  - guerrilla 7y ago
    Where does one check that?
    - tunesmith 7y ago
      Here's a seemingly reputable source? https://twitter.com/trvrb/status/1238310251679461377 https://twitter.com/trvrb/status/1238310251679461377
cycrutchfield 7y ago
> prior to 23 January 2020 travel restrictions So, no.
- nmca 7y ago
  Could you elaborate?
  - nmca 7y ago
    Ah, you imply that the underreporting rate fell over time and the headline number is from before the travel ban.
    - cycrutchfield 7y ago
      Precisely
  - cycrutchfield 7y ago
    >Overall, our findings indicate that a large proportion of COVID-19 infections were undocumented prior to the implementation of travel restrictions and other heightened control measures in China on 23 January, and that a large proportion of the total force of infection was mediated through these undocumented infections (Table 1). This high proportion of undocumented infections, many of whom were likely not severely symptomatic, appears to have facilitated the rapid spread of the virus throughout China. Indeed, suppression of the infectiousness of these undocumented cases in model simulations reduces the total number of documented cases and the overall spread of SARS-CoV2 This paper is about undetected carriers spreading SARS-CoV2 across China prior to the Jan 23 lockdown. It does not imply that 86% of all total infections that we see currently are undocumented, it only reflects the relatively narrow testing that was happening prior to Jan 23 (likely only the severe cases). After Jan 23, China expanded its testing much more broadly, and other countries (such as South Korea) have done so as well. You should not take this paper to mean that the actual number of cases for these countries is larger by a factor of 1/(1-0.86).
    - nmca 7y ago
oarabbus_ 7y ago
> assume that number of unreported fatal cases is 0 While I agree with your overall point, I don't believe this is a good assumption. I think some percentage of unreported fatal cases are reported as pneumonia/cardiac arrest/etc.
- deleted 7y ago
  [deleted]
httpz 7y ago
Assuming that someone who died from coronavirus is far more likely to have been tested for the virus than someone who's been infected by it, the true death rate of someone infected by the virus is probably far lower than the calculated death rate. (# of confirmed death / # of confirmed infections). S.Korea did extensive testing, which reduces the number of unreported infections. So the calculated death rate in S. Korea is 4x lower than a comparable country like Spain, which has similar # of confirmed cases, population, GDP, and GDP per capita. If we assume S. Korea's calculated death rate(<1%) is closer to the true death rate and apply it to other countries to derive the total # of infections (reported + unreported) based on the reported death count, we can see there may be far more infections than we know.
- cycrutchfield 7y ago
  This is not really valid due to fatality rate being heavily dependent on age, comorbidities, and healthcare quality (which is itself dependent on case load), and the distributions of these differ greatly across countries. But, sure, you could try to normalize these to infer the actual case load.
  - httpz 7y ago
    There is a lot of assuming going on so this doesn't actually prove anything but I think it's something worth thinking about. Is Spain and S. Korea really that much different to have a 4x difference in death rate?
  - danielheath 7y ago
    Right - eg when the ICU is full and refusing new patients, the death rate is going to be higher.
  - TheOtherHobbes 7y ago
    It would be useful if this could be broken down into separate categories - estimated CFR without medical intervention, and likely CFR at various levels of intervention. The former suggests what your population mortality rate will be if your healthcare system is overwhelmed, and could possibly be derived from Italian data. The latter gives you a resources vs effectiveness sweet spot that maximises health system throughput, so you can save the maximum number of lives over time given the resources you have (or can build/find.) The age profile is relevant, but worryingly there seem to be a number of reports that it's not just the over-65s who are at risk. I haven't seen anything more recent about this than the Chinese estimates from a month or so ago.
rockinghigh 7y ago
No, it does not mean the mortality rate is 10x lower because dead people who were not tested also don't get counted in the rate.
- eanzenberg 7y ago
  I don't know how your body isn't tested for coronavirus if you've died in the past 2 months in the western world
usrusr 7y ago
Mortality rate depends a lot on treatment circumstances and the difference between optimal treatment and zero treatment could easily exceed the uncertainty from undocumented infections. This makes trying to figure out a single true mortality rate kind of pointless.
- learc83 7y ago
  It's not just death rate, but the rate at which it becomes severe. South Korea's severe case rate is also much lower than other countries. The most likely explanation is that Korea is catching more mild cases that other countries are missing.
aidos 7y ago
In the UK they only found 1,543 cases from 44,000 tests. That would seem to imply they're either incredibly unlucky with the testing, or it's not as quietly widespread as one might hope.
- arcticbull 7y ago
  If uniformally randomly distributed that would imply a 3% population infection rate today, with an R0 of 2-3, 100% of the population either has had it or will have it by the end of next week. That would be wildly past the tipping point. Until we have an antibody test we can only know who has it right now, if you’ve had it more than 2 weeks ago you’re not going to test positive.
  - aidos 7y ago
    I’m not going to argue on the statistics, because I don’t quite get it. You seem to be implying that maybe there are a load of us that had it already (and maybe, hopefully, that’s the case). But if so, doesn’t it seem weird that we’ve basically watched its progress as it’s spread around the world? Why would most people get it and be asymptotic followed by a series of unlucky people that are getting it now and falling ill? Though again, maybe I’m misunderstanding.
    - arcticbull 7y ago
      I'm kinda spitballing here too. > You seem to be implying that maybe there are a load of us that had it already (and maybe, hopefully, that’s the case). Yep, and that as a result our mortality projections from CFR are quite overstated. > But if so, doesn’t it seem weird that we’ve basically watched its progress as it’s spread around the world? I wouldn't be shocked to see a retrospective on this in the future tell us that we've been seeing the spread of availability of the test rather than the disease. > Why would most people get it and be asymptotic followed by a series of unlucky people that are getting it now and falling ill? Symptoms are basically the same as the flu for most people (Korea has a 0% CFR under 29, and 0.1% under 49), and for older folks, well, they're older, and basically anything can kill them. Some studies showed a fatality rate of 10% for the H1N1 flu -- and so far we're seeing a CFR of 15% for old folks in Korea. It's possible the fatalities we'd been seeing were written off as just that.
Gatsky 7y ago
The mortality rate is definitely lower than anything being measured. But the lower bound is still high enough that this is very bad, maybe just not 'blight of the eons, scourge of humanity' level. If you are above 70 or have health problems, the mortality rate is extremely bad whatever the real number is.
- catalogia 7y ago
  > If you are above 70 or have health problems, the mortality rate is extremely bad According to this article (https://www.businessinsider.com/coronavirus-death-age-older-people-higher-risk-2020-2?op=1 https://www.businessinsider.com/coronavirus-death-age-older-...) an 80 year old has a 15% chance of dying. Is that actually "extremely bad" though? I think if 80 year old grandma got cancer and the doctors told you there was a 85% chance she'd recover, you might well breath a sigh of relief. For somebody that old, there are much worse mortality rates than that. Breaking your hip is more deadly than getting the coronavirus for people that old[0]. Rather the legitimate concern is due to how rapidly the disease is spreading. 15% is enough to kill TONS of people when you scale it up to the whole population. It's a high mortality rate considering the scope of the pandemic, but a relatively low mortality rate for the individual. [0] "The risk of death in the year following a fracture is about 20% in older people." https://en.wikipedia.org/wiki/Hip_fracture https://en.wikipedia.org/wiki/Hip_fracture
  - adventured 7y ago
    > an 80 year old has a 15% chance of dying. Is that actually "extremely bad" though? Yes.
    - catalogia 7y ago
      Care to convince me?
      - bhaak 7y ago
        How would you feel about being in a group of 7 of which one gets randomly shot? How much money would I have to offer you that you took your chances? Unnecessary deaths are worse than life threats you can't do anything about it.

by nmca 7y ago

nmca 7y ago

I have been considering other ways to estimate this, and looked at numbers for Singapore, which I believe has particularly strict testing. They show a much lower mortality rate than the other estimates I have heard, but only at n=250. This may also be confounded by wealth/healthcare quality. Does anyone have a decent model of the mortality rate?

arcticbull 7y ago

Yeah so, what the data has been pointing to the whole time.

cycrutchfield 7y ago
Which data?
- arcticbull 7y ago
  Well the cruise ship showed 55% of folks being asymptomatic and 80% of the remainder have mild flu like symptoms, and with an R0 of 2-3 for every person you do see get tested positive, there’s a mountain of folks spreading it without symptoms. This also explains why Korea’s [edit: case fatality] rate is so low and so correlated with their high incidence of testing. I wouldn’t be surprised if the majority of us have already had it. There’s a decent shot this all amounts to a big ol nothing burger.
  - bathtub365 7y ago
    Despite all experts saying it is actually a big problem? It's a disease that spreads rapidly and kills people who wouldn't otherwise have died. That doesn't sound like nothing to me.
    - arcticbull 7y ago
      It tends to work out better for those who overstate threat than those who understate, both in the moment (you get more attention) and after (if you’re right you get yet more attention, and if you were wrong everyone gives you a pass due to the mass collective panic).
  - cycrutchfield 7y ago
    Korea's mortality rate is about 1%, and that is primarily due to a relatively youthful population and the healthcare system not being saturated. I'll also note that 1% is still 10x deadlier than the flu. It sounds like you may be interested in reading this paper: https://www.medrxiv.org/content/10.1101/2020.03.04.20031104v1.full.pdf https://www.medrxiv.org/content/10.1101/2020.03.04.20031104v... >I wouldn’t be surprised if the majority of us have already had it. There’s a decent shot this all amounts to a big ol nothing burger. Unsupported by any evidence and complete wishful thinking. Please stop with the irresponsible speculation.
    - MikeAmelung 7y ago
      You don't know the difference between case fatality rate and mortality rate, so maybe you should stop with the irresponsible speculation.
      - cycrutchfield 7y ago
        I was just using the language of the person I was replying to. Would you like to be more pedantic?
        7y ago

nerdface 7y ago

What I wonder is, does this mean deaths are also under reported because they're being attributed to the flu or pneumonia without adequate testing?

learc83 7y ago
A few maybe, but there haven't been large numbers of additional pneumonia deaths beyond those attributed to coronavirus.
- guerrilla 7y ago
  Where does one check that?
  - tunesmith 7y ago
    Here's a seemingly reputable source? https://twitter.com/trvrb/status/1238310251679461377 https://twitter.com/trvrb/status/1238310251679461377

cycrutchfield 7y ago

> prior to 23 January 2020 travel restrictions So, no.

nmca 7y ago
Could you elaborate?
- nmca 7y ago
  Ah, you imply that the underreporting rate fell over time and the headline number is from before the travel ban.
  - cycrutchfield 7y ago
    Precisely
- cycrutchfield 7y ago
  >Overall, our findings indicate that a large proportion of COVID-19 infections were undocumented prior to the implementation of travel restrictions and other heightened control measures in China on 23 January, and that a large proportion of the total force of infection was mediated through these undocumented infections (Table 1). This high proportion of undocumented infections, many of whom were likely not severely symptomatic, appears to have facilitated the rapid spread of the virus throughout China. Indeed, suppression of the infectiousness of these undocumented cases in model simulations reduces the total number of documented cases and the overall spread of SARS-CoV2 This paper is about undetected carriers spreading SARS-CoV2 across China prior to the Jan 23 lockdown. It does not imply that 86% of all total infections that we see currently are undocumented, it only reflects the relatively narrow testing that was happening prior to Jan 23 (likely only the severe cases). After Jan 23, China expanded its testing much more broadly, and other countries (such as South Korea) have done so as well. You should not take this paper to mean that the actual number of cases for these countries is larger by a factor of 1/(1-0.86).
  - nmca 7y ago

oarabbus_ 7y ago

> assume that number of unreported fatal cases is 0 While I agree with your overall point, I don't believe this is a good assumption. I think some percentage of unreported fatal cases are reported as pneumonia/cardiac arrest/etc.

deleted 7y ago
[deleted]

httpz 7y ago

Assuming that someone who died from coronavirus is far more likely to have been tested for the virus than someone who's been infected by it, the true death rate of someone infected by the virus is probably far lower than the calculated death rate. (# of confirmed death / # of confirmed infections). S.Korea did extensive testing, which reduces the number of unreported infections. So the calculated death rate in S. Korea is 4x lower than a comparable country like Spain, which has similar # of confirmed cases, population, GDP, and GDP per capita. If we assume S. Korea's calculated death rate(<1%) is closer to the true death rate and apply it to other countries to derive the total # of infections (reported + unreported) based on the reported death count, we can see there may be far more infections than we know.

cycrutchfield 7y ago
This is not really valid due to fatality rate being heavily dependent on age, comorbidities, and healthcare quality (which is itself dependent on case load), and the distributions of these differ greatly across countries. But, sure, you could try to normalize these to infer the actual case load.
- httpz 7y ago
  There is a lot of assuming going on so this doesn't actually prove anything but I think it's something worth thinking about. Is Spain and S. Korea really that much different to have a 4x difference in death rate?
- danielheath 7y ago
  Right - eg when the ICU is full and refusing new patients, the death rate is going to be higher.
- TheOtherHobbes 7y ago
  It would be useful if this could be broken down into separate categories - estimated CFR without medical intervention, and likely CFR at various levels of intervention. The former suggests what your population mortality rate will be if your healthcare system is overwhelmed, and could possibly be derived from Italian data. The latter gives you a resources vs effectiveness sweet spot that maximises health system throughput, so you can save the maximum number of lives over time given the resources you have (or can build/find.) The age profile is relevant, but worryingly there seem to be a number of reports that it's not just the over-65s who are at risk. I haven't seen anything more recent about this than the Chinese estimates from a month or so ago.

rockinghigh 7y ago

No, it does not mean the mortality rate is 10x lower because dead people who were not tested also don't get counted in the rate.

eanzenberg 7y ago
I don't know how your body isn't tested for coronavirus if you've died in the past 2 months in the western world

usrusr 7y ago

Mortality rate depends a lot on treatment circumstances and the difference between optimal treatment and zero treatment could easily exceed the uncertainty from undocumented infections. This makes trying to figure out a single true mortality rate kind of pointless.

learc83 7y ago
It's not just death rate, but the rate at which it becomes severe. South Korea's severe case rate is also much lower than other countries. The most likely explanation is that Korea is catching more mild cases that other countries are missing.

aidos 7y ago

In the UK they only found 1,543 cases from 44,000 tests. That would seem to imply they're either incredibly unlucky with the testing, or it's not as quietly widespread as one might hope.

arcticbull 7y ago
If uniformally randomly distributed that would imply a 3% population infection rate today, with an R0 of 2-3, 100% of the population either has had it or will have it by the end of next week. That would be wildly past the tipping point. Until we have an antibody test we can only know who has it right now, if you’ve had it more than 2 weeks ago you’re not going to test positive.
- aidos 7y ago
  I’m not going to argue on the statistics, because I don’t quite get it. You seem to be implying that maybe there are a load of us that had it already (and maybe, hopefully, that’s the case). But if so, doesn’t it seem weird that we’ve basically watched its progress as it’s spread around the world? Why would most people get it and be asymptotic followed by a series of unlucky people that are getting it now and falling ill? Though again, maybe I’m misunderstanding.
  - arcticbull 7y ago
    I'm kinda spitballing here too. > You seem to be implying that maybe there are a load of us that had it already (and maybe, hopefully, that’s the case). Yep, and that as a result our mortality projections from CFR are quite overstated. > But if so, doesn’t it seem weird that we’ve basically watched its progress as it’s spread around the world? I wouldn't be shocked to see a retrospective on this in the future tell us that we've been seeing the spread of availability of the test rather than the disease. > Why would most people get it and be asymptotic followed by a series of unlucky people that are getting it now and falling ill? Symptoms are basically the same as the flu for most people (Korea has a 0% CFR under 29, and 0.1% under 49), and for older folks, well, they're older, and basically anything can kill them. Some studies showed a fatality rate of 10% for the H1N1 flu -- and so far we're seeing a CFR of 15% for old folks in Korea. It's possible the fatalities we'd been seeing were written off as just that.

Gatsky 7y ago

The mortality rate is definitely lower than anything being measured. But the lower bound is still high enough that this is very bad, maybe just not 'blight of the eons, scourge of humanity' level. If you are above 70 or have health problems, the mortality rate is extremely bad whatever the real number is.

catalogia 7y ago
> If you are above 70 or have health problems, the mortality rate is extremely bad According to this article (https://www.businessinsider.com/coronavirus-death-age-older-people-higher-risk-2020-2?op=1 https://www.businessinsider.com/coronavirus-death-age-older-...) an 80 year old has a 15% chance of dying. Is that actually "extremely bad" though? I think if 80 year old grandma got cancer and the doctors told you there was a 85% chance she'd recover, you might well breath a sigh of relief. For somebody that old, there are much worse mortality rates than that. Breaking your hip is more deadly than getting the coronavirus for people that old[0]. Rather the legitimate concern is due to how rapidly the disease is spreading. 15% is enough to kill TONS of people when you scale it up to the whole population. It's a high mortality rate considering the scope of the pandemic, but a relatively low mortality rate for the individual. [0] "The risk of death in the year following a fracture is about 20% in older people." https://en.wikipedia.org/wiki/Hip_fracture https://en.wikipedia.org/wiki/Hip_fracture
- adventured 7y ago
  > an 80 year old has a 15% chance of dying. Is that actually "extremely bad" though? Yes.
  - catalogia 7y ago
    Care to convince me?
    - bhaak 7y ago
      How would you feel about being in a group of 7 of which one gets randomly shot? How much money would I have to offer you that you took your chances? Unnecessary deaths are worse than life threats you can't do anything about it.