5 ms·

How Bad Is the Coronavirus? Let’s Run the Numbers

71 points by kqr2 7y ago

deleted 7y ago
[deleted]
cmdshiftf4 7y ago
Why does a blog post require 14 sources of javascript? Will await a mirror.
zaroth 7y ago
This article does a better job than most, but I think still only half-asses the thought process necessary to logically reason about COVID. The naive or “known” CFR is the fatality rate to-date divided by the number of positive tests to date. For example, China at one point decided to consider a large number of people as positive cases based on purely clinical symptoms because they didn’t have the test capacity or specificity to definitively diagnose them. Which is why their case count gapped up one day. The CFR after all cases have concluded is an upper bound on the IFR. There seems to be no true consensus on the percentage of asymptomatic or very mild cases which would not seek treatment or even testing. This number (which is basically unknowable during an outbreak) is a multiplier on the case count, and acts to reduce the true IFR. Lastly, as we’ve seen quite clearly... How bad it is depends almost entirely upon the person, or at a higher level, the demographics of the people who are infected. Italy as of March 11; > Of the patients who died, 42·2% were aged 80–89 years, 32·4% were aged 70–79 years, 8·4% were aged 60–69 years, and 2·8% were aged 50–59 years (those aged >90 years made up 14·1%). The male to female ratio is 80% to 20% with an older median age for women (83·4 years for women vs 79·9 years for men). Likewise, the outbreak in a WA nursing home was devastating to an elderly population where they would see 5-10 patients die in an average month. IMO the path forward is either successful containment—which seems extremely unlikely given the transmission characteristics, but apparently China was able to do it? But where you constantly have to be watching for pockets of reemergence and clamp them down. Or, if we can keep the virus away from high-risk populations while it spreads “like a flu” through the majority of the population, then you will see herd immunity kick in which ultimately works like a vaccinated population to prevent further outbreak and protect the at-risk population from ever becoming infected. [1] - https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)30627-9/fulltext https://www.thelancet.com/journals/lancet/article/PIIS0140-6...
- empath75 7y ago
  China’s method of containment was to scan pretty much the entire population for fever and quarantine everyone who might have been infected immediately and involuntarily, including taking children from parents. Needless to say, that will never happen in the us or Europe.
  - zaroth 7y ago
    And what’s your thought for explaining South Korea?
    - empath75 7y ago
      They did extensive testing and containment but that won’t matter eventually. It will break out into unchecked community spread eventually unless they implement a similar quarantine.
  - alfiedotwtf 7y ago
    > taking children from parents. Needless to say, that will never happen in the US They separated Native American and immigrant families in the recent past, why stop now
    - Fjolsvith 7y ago
      Don't know about the Native Americans, but the immigrants who broke the law by entering illegally had as much right to remain with their children as a US Citizen arrested for a DUI - i.e. none until released from custody.
- pmoriarty 7y ago
  "How bad it is depends almost entirely upon the person, or at a higher level, the demographics of the people who are infected." There are other important factors to consider. There will be a percentage of infected individuals who otherwise would have survived had they had access to respiratory assistance by trained medical staff at a hospital. But as medical staff get overwhelmed, get sick, or die, as free room in Intensive Care Units is used up, as respiratory assistance technology becomes unavailable because it's busy supporting other patients, the death rate will rise beyond what looking at the demographic data alone might lead one to believe. In addition, there are likely to be extra deaths from other, completely unrelated diseases and conditions for which people can no longer get treatment as hospitals and medical staff get overwhelmed, and as we run in to medicine and medical equipment shortages from lack of supply in China (and, I expect before long, from India and other countries on which the US medical system relies). To make matters worse, the people sick with COVID-19 will likely infect a lot of vulnerable patients in the hospitals they go to, as most hospitals just simply aren't equipped to effectively contain such infections, especially when there are so many of them. This will increase the death toll even further. There are many group living facilities such as prisons and nursing homes which will likely be affected by this as well. They will be especially vulnerable because the people there tend to already not be in the healthiest shape and have weakened immune systems.
casefields 7y ago
Mirror: http://archive.md/fyPMl http://archive.md/fyPMl
lucas_membrane 7y ago
tldr: This article leaves off about where a similar report on epidemiological models did a couple of weeks ago: Covid-19 will be very very hard to control if persons showing no symptoms spread the disease too often, but we do not know whether or not they do.
- avocado4 7y ago
  This article does explicitly discuss pre-symptomatic transmission, specifically it being worse than SARS but better than flu in that regard.
brink 7y ago
One question that's been on my mind: The number of Coronavirus cases is likely far more than what's being reported. Apparently there are those who get coronavirus and are unaware that they have it before they heal. However everyone that dies of coronavirus is reported as a coronavirus case. Does this mean that there's a good chance the death rate is lower than the current calculated 3% with so many recoveries going unreported?
- marshallant 7y ago
  And I would like to know how many people have died not due to coronavirus but it was labeled so because they just happened to have it when they passed away.
- Mountain_Skies 7y ago
  Isn't also true for influenza? I had flu symptoms back in January but other than telling my manager that I was going to be out of the office due to illness, never reported my flu to anyone. Doubt I'm the only one who did this.
  - learc83 7y ago
    Yes this happens, but for the flu we have done large scale antibody studies, so we have an idea that for every x number of people who get treated, y number are actually infected. The problem is we don't have the same data for this virus yet.
  - zaroth 7y ago
    CDC estimates the total number of flu infections at about 10-20% of the population, depending on the year. The total number of hospital cases is usually ~1-2% of the number of infections. The, e.g. “32 million cases of flu” reported by the CDC is not based on 32 million positive test results. It’s extrapolated based on a factor of how many cases require hospitalization, and how many people seek medical care, which itself is based on antibody and behavioral surveys. > The numbers of influenza illnesses were estimated from hospitalizations based on how many illnesses there are for every hospitalization, which was measured previously (5). > Some people with influenza will seek medical care, while others will not. CDC estimates the number of people who sought medical care for influenza using data from the 2010 Behavioral Risk Factor Surveillance Survey, which asked people whether they did or did not seek medical care for an influenza-like illness in the prior influenza season (6). After reading more about it [1] you almost wonder how much better than a WAG (“Wild Ass Guess”) it really is. Frankly I am finding this whole area of medical science entirely underwhelming relative to the potential impact to lives and economies of the world. https://www.cdc.gov/flu/about/burden/how-cdc-estimates.htm https://www.cdc.gov/flu/about/burden/how-cdc-estimates.htm
marshallant 7y ago
I find it odd we don't hear anything about the mild cases. If I didn't know any better I would assume if I got coronavirus I would be on my death bed.
booleandilemma 7y ago
At this point I’m more worried about food, water, and toilet paper shortages due to people hoarding 20 times more than what they need. The virus itself doesn’t sound too bad if you’re under 70.
- deleted 7y ago
  [deleted]
- empath75 7y ago
  Even for people under 40, it’s 20 times deadlier than the flu is.
  - mitchdoogle 7y ago
    People don't need numbers any more. It's only going to matter to some people if someone they view as a 'healthy, normal' person tests positive. Even more of a freak-out if someone like that dies. If a famous celebrity or athlete gets were to die from this, it would set off a lot more worrying
    - wincy 7y ago
      Imagine how tortured you’d be as the doctor that let Tom Hanks die. If he dies people will freak out.
  - avocado4 7y ago
    Do you have a source for that?
    - greedo 7y ago
      https://ourworldindata.org/coronavirus https://ourworldindata.org/coronavirus has some excellent information.
  - deleted 7y ago
    [deleted]
- 7y ago
travisporter 7y ago
This guy did some back of the envelope calcs I found interesting/scary https://medium.com/@tomaspueyo/coronavirus-act-today-or-people-will-die-f4d3d9cd99ca https://medium.com/@tomaspueyo/coronavirus-act-today-or-peop...
- williamstein 7y ago
  Thanks for posting this. It's exactly the sort of analysis I would want to do if I had way more time, and he explains his reasoning completely in a way that a non expert can understand (and provides his models), perhaps because he is not a professional epidemiologist.
  - jorisw 7y ago
    Meaning the calculations are worthless.
pmoriarty 7y ago
From a Penn State epidemiologist (note that the quote below speaks of the "infection fatality rate", which is different from the "case fatality rate", the difference is explained in the article)[1]: "Scientists working at the London School of Hygiene and Tropical Medicine, Imperial College London and the Institute for Disease Modeling have used these approaches to estimate the infection fatality rate. Currently, these estimates range from 0.5% to 0.94% indicating that COVID-19 is about 10 to 20 times as deadly as seasonal influenza. Evidence coming in from genomics and large-scale testing of fevers is consistent with these conclusions. The only potentially good news is that the epidemic in Korea may ultimately show a lower CFR than the epidemic in China. ... "On balance, it is reasonable to guess that COVID-19 will infect as many Americans over the next year as influenza does in a typical winter -- somewhere between 25 million and 115 million. Maybe a bit more if the virus turns out to be more contagious than we thought. Maybe a bit less if we put restrictions in place that minimize our travel and our social and professional contacts. "The bad news is, of course, that these infection numbers translate to 350,000 to 660,000 people dying in the U.S., with an uncertainty range that goes from 50,000 deaths to 5 million deaths. The good news is that this is not a weather forecast. The size of the epidemic, i.e., the total number of infections, is something we can reduce if we decrease our contact patterns and improve our hygiene. If the total number of infections decreases, the total number of deaths will also decrease." [1] - https://www.marketwatch.com/story/why-this-epidemiologist-is-more-worried-about-coronavirus-than-he-was-a-month-ago-2020-03-09 https://www.marketwatch.com/story/why-this-epidemiologist-is...
throwaway_pdp09 7y ago
A general question to all. Disclaimer, I'm no epidemiologist and not even a statistician. I may totally misunderstand something here. That said, I copied the data from the US, UK and Italy on cases (go to https://en.wikipedia.org/wiki/2019%E2%80%9320_outbreak_of_novel_coronavirus_%282019-nCoV%29 https://en.wikipedia.org/wiki/2019%E2%80%9320_outbreak_of_no... and click on the relevant flag in the table, copy the data off the graph, scrub with regexes). I dumped this into Tableau, graphed it and put an exponential trend line over the top. The UK and US data dropped almost perfectly onto an exponential (R-squared > 0.99 for both, P value better than 0.0001 for both, whatever those mean). The visual fit was remarkably good. The italian data very obviously did not fit so well. It clearly was flatter than the best fit exponential (strange, given that covid is totally ablaze there) and it had an R-squared of 0.946, though it's P value was still less than 0.0001. Can anyone comment? The raw data for italy is below. date,cases 2020-02-21,20 2020-02-22,79 2020-02-23,150 2020-02-24,227 2020-02-25,320 2020-02-26,445 2020-02-27,650 2020-02-28,888 2020-02-29,1128 2020-03-01,1694 2020-03-02,2036 2020-03-03,2502 2020-03-04,3089 2020-03-05,3858 2020-03-06,4636 2020-03-07,5883 2020-03-08,7375 2020-03-09,9172 2020-03-10,10149 2020-03-11,12462 2020-03-12,15113 2020-03-13,17660 2020-03-14,21157 Edit: for comparison, US data is below. date,cases 2020-02-26,15 2020-02-27,15 2020-02-28,19 2020-02-29,24 2020-03-01,42 2020-03-02,57 2020-03-03,85 2020-03-04,111 2020-03-05,175 2020-03-06,252 2020-03-07,352 2020-03-08,495 2020-03-09,643 2020-03-10,911 2020-03-11,1182 2020-03-12,1577 2020-03-13,2184 2020-03-14,2628
- maxerickson 7y ago
  A possible explanation is that their testing can't keep up with the spread. ~13,000 test per day for the last several days, with more positive results yesterday for the same number of tests.
  - throwaway_pdp09 7y ago
    If true that would apply much more to the US data, where I understand the amount of testing has been extremely low. In any case the data is surely of confirmed cases, so these have got past the testing, no? And I'm not sure if that would produce a flatter-than-exponential curve, which seems to be what it is.
jorisw 7y ago
Justin Fox is a Bloomberg Opinion columnist covering business. A total layman on the subject matter. Stop writing about corona if you’re not an expert. Stop reading and sharing non-expert opinions.

71 points by kqr2 7y ago

deleted 7y ago

[deleted]

cmdshiftf4 7y ago

Why does a blog post require 14 sources of javascript? Will await a mirror.

zaroth 7y ago

This article does a better job than most, but I think still only half-asses the thought process necessary to logically reason about COVID. The naive or “known” CFR is the fatality rate to-date divided by the number of positive tests to date. For example, China at one point decided to consider a large number of people as positive cases based on purely clinical symptoms because they didn’t have the test capacity or specificity to definitively diagnose them. Which is why their case count gapped up one day. The CFR after all cases have concluded is an upper bound on the IFR. There seems to be no true consensus on the percentage of asymptomatic or very mild cases which would not seek treatment or even testing. This number (which is basically unknowable during an outbreak) is a multiplier on the case count, and acts to reduce the true IFR. Lastly, as we’ve seen quite clearly... How bad it is depends almost entirely upon the person, or at a higher level, the demographics of the people who are infected. Italy as of March 11; > Of the patients who died, 42·2% were aged 80–89 years, 32·4% were aged 70–79 years, 8·4% were aged 60–69 years, and 2·8% were aged 50–59 years (those aged >90 years made up 14·1%). The male to female ratio is 80% to 20% with an older median age for women (83·4 years for women vs 79·9 years for men). Likewise, the outbreak in a WA nursing home was devastating to an elderly population where they would see 5-10 patients die in an average month. IMO the path forward is either successful containment—which seems extremely unlikely given the transmission characteristics, but apparently China was able to do it? But where you constantly have to be watching for pockets of reemergence and clamp them down. Or, if we can keep the virus away from high-risk populations while it spreads “like a flu” through the majority of the population, then you will see herd immunity kick in which ultimately works like a vaccinated population to prevent further outbreak and protect the at-risk population from ever becoming infected. [1] - https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)30627-9/fulltext https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

empath75 7y ago
China’s method of containment was to scan pretty much the entire population for fever and quarantine everyone who might have been infected immediately and involuntarily, including taking children from parents. Needless to say, that will never happen in the us or Europe.
- zaroth 7y ago
  And what’s your thought for explaining South Korea?
  - empath75 7y ago
    They did extensive testing and containment but that won’t matter eventually. It will break out into unchecked community spread eventually unless they implement a similar quarantine.
- alfiedotwtf 7y ago
  > taking children from parents. Needless to say, that will never happen in the US They separated Native American and immigrant families in the recent past, why stop now
  - Fjolsvith 7y ago
    Don't know about the Native Americans, but the immigrants who broke the law by entering illegally had as much right to remain with their children as a US Citizen arrested for a DUI - i.e. none until released from custody.
pmoriarty 7y ago
"How bad it is depends almost entirely upon the person, or at a higher level, the demographics of the people who are infected." There are other important factors to consider. There will be a percentage of infected individuals who otherwise would have survived had they had access to respiratory assistance by trained medical staff at a hospital. But as medical staff get overwhelmed, get sick, or die, as free room in Intensive Care Units is used up, as respiratory assistance technology becomes unavailable because it's busy supporting other patients, the death rate will rise beyond what looking at the demographic data alone might lead one to believe. In addition, there are likely to be extra deaths from other, completely unrelated diseases and conditions for which people can no longer get treatment as hospitals and medical staff get overwhelmed, and as we run in to medicine and medical equipment shortages from lack of supply in China (and, I expect before long, from India and other countries on which the US medical system relies). To make matters worse, the people sick with COVID-19 will likely infect a lot of vulnerable patients in the hospitals they go to, as most hospitals just simply aren't equipped to effectively contain such infections, especially when there are so many of them. This will increase the death toll even further. There are many group living facilities such as prisons and nursing homes which will likely be affected by this as well. They will be especially vulnerable because the people there tend to already not be in the healthiest shape and have weakened immune systems.

casefields 7y ago

Mirror: http://archive.md/fyPMl http://archive.md/fyPMl

lucas_membrane 7y ago

tldr: This article leaves off about where a similar report on epidemiological models did a couple of weeks ago: Covid-19 will be very very hard to control if persons showing no symptoms spread the disease too often, but we do not know whether or not they do.

avocado4 7y ago
This article does explicitly discuss pre-symptomatic transmission, specifically it being worse than SARS but better than flu in that regard.

brink 7y ago

One question that's been on my mind: The number of Coronavirus cases is likely far more than what's being reported. Apparently there are those who get coronavirus and are unaware that they have it before they heal. However everyone that dies of coronavirus is reported as a coronavirus case. Does this mean that there's a good chance the death rate is lower than the current calculated 3% with so many recoveries going unreported?

marshallant 7y ago
And I would like to know how many people have died not due to coronavirus but it was labeled so because they just happened to have it when they passed away.
Mountain_Skies 7y ago
Isn't also true for influenza? I had flu symptoms back in January but other than telling my manager that I was going to be out of the office due to illness, never reported my flu to anyone. Doubt I'm the only one who did this.
- learc83 7y ago
  Yes this happens, but for the flu we have done large scale antibody studies, so we have an idea that for every x number of people who get treated, y number are actually infected. The problem is we don't have the same data for this virus yet.
- zaroth 7y ago
  CDC estimates the total number of flu infections at about 10-20% of the population, depending on the year. The total number of hospital cases is usually ~1-2% of the number of infections. The, e.g. “32 million cases of flu” reported by the CDC is not based on 32 million positive test results. It’s extrapolated based on a factor of how many cases require hospitalization, and how many people seek medical care, which itself is based on antibody and behavioral surveys. > The numbers of influenza illnesses were estimated from hospitalizations based on how many illnesses there are for every hospitalization, which was measured previously (5). > Some people with influenza will seek medical care, while others will not. CDC estimates the number of people who sought medical care for influenza using data from the 2010 Behavioral Risk Factor Surveillance Survey, which asked people whether they did or did not seek medical care for an influenza-like illness in the prior influenza season (6). After reading more about it [1] you almost wonder how much better than a WAG (“Wild Ass Guess”) it really is. Frankly I am finding this whole area of medical science entirely underwhelming relative to the potential impact to lives and economies of the world. https://www.cdc.gov/flu/about/burden/how-cdc-estimates.htm https://www.cdc.gov/flu/about/burden/how-cdc-estimates.htm

marshallant 7y ago

I find it odd we don't hear anything about the mild cases. If I didn't know any better I would assume if I got coronavirus I would be on my death bed.

booleandilemma 7y ago

At this point I’m more worried about food, water, and toilet paper shortages due to people hoarding 20 times more than what they need. The virus itself doesn’t sound too bad if you’re under 70.

deleted 7y ago
[deleted]
empath75 7y ago
Even for people under 40, it’s 20 times deadlier than the flu is.
- mitchdoogle 7y ago
  People don't need numbers any more. It's only going to matter to some people if someone they view as a 'healthy, normal' person tests positive. Even more of a freak-out if someone like that dies. If a famous celebrity or athlete gets were to die from this, it would set off a lot more worrying
  - wincy 7y ago
    Imagine how tortured you’d be as the doctor that let Tom Hanks die. If he dies people will freak out.
- avocado4 7y ago
  Do you have a source for that?
  - greedo 7y ago
    https://ourworldindata.org/coronavirus https://ourworldindata.org/coronavirus has some excellent information.
- deleted 7y ago
  [deleted]
7y ago

travisporter 7y ago

This guy did some back of the envelope calcs I found interesting/scary https://medium.com/@tomaspueyo/coronavirus-act-today-or-people-will-die-f4d3d9cd99ca https://medium.com/@tomaspueyo/coronavirus-act-today-or-peop...

williamstein 7y ago
Thanks for posting this. It's exactly the sort of analysis I would want to do if I had way more time, and he explains his reasoning completely in a way that a non expert can understand (and provides his models), perhaps because he is not a professional epidemiologist.
- jorisw 7y ago
  Meaning the calculations are worthless.

pmoriarty 7y ago

From a Penn State epidemiologist (note that the quote below speaks of the "infection fatality rate", which is different from the "case fatality rate", the difference is explained in the article)[1]: "Scientists working at the London School of Hygiene and Tropical Medicine, Imperial College London and the Institute for Disease Modeling have used these approaches to estimate the infection fatality rate. Currently, these estimates range from 0.5% to 0.94% indicating that COVID-19 is about 10 to 20 times as deadly as seasonal influenza. Evidence coming in from genomics and large-scale testing of fevers is consistent with these conclusions. The only potentially good news is that the epidemic in Korea may ultimately show a lower CFR than the epidemic in China. ... "On balance, it is reasonable to guess that COVID-19 will infect as many Americans over the next year as influenza does in a typical winter -- somewhere between 25 million and 115 million. Maybe a bit more if the virus turns out to be more contagious than we thought. Maybe a bit less if we put restrictions in place that minimize our travel and our social and professional contacts. "The bad news is, of course, that these infection numbers translate to 350,000 to 660,000 people dying in the U.S., with an uncertainty range that goes from 50,000 deaths to 5 million deaths. The good news is that this is not a weather forecast. The size of the epidemic, i.e., the total number of infections, is something we can reduce if we decrease our contact patterns and improve our hygiene. If the total number of infections decreases, the total number of deaths will also decrease." [1] - https://www.marketwatch.com/story/why-this-epidemiologist-is-more-worried-about-coronavirus-than-he-was-a-month-ago-2020-03-09 https://www.marketwatch.com/story/why-this-epidemiologist-is...

throwaway_pdp09 7y ago

A general question to all. Disclaimer, I'm no epidemiologist and not even a statistician. I may totally misunderstand something here. That said, I copied the data from the US, UK and Italy on cases (go to https://en.wikipedia.org/wiki/2019%E2%80%9320_outbreak_of_novel_coronavirus_%282019-nCoV%29 https://en.wikipedia.org/wiki/2019%E2%80%9320_outbreak_of_no... and click on the relevant flag in the table, copy the data off the graph, scrub with regexes). I dumped this into Tableau, graphed it and put an exponential trend line over the top. The UK and US data dropped almost perfectly onto an exponential (R-squared > 0.99 for both, P value better than 0.0001 for both, whatever those mean). The visual fit was remarkably good. The italian data very obviously did not fit so well. It clearly was flatter than the best fit exponential (strange, given that covid is totally ablaze there) and it had an R-squared of 0.946, though it's P value was still less than 0.0001. Can anyone comment? The raw data for italy is below. date,cases 2020-02-21,20 2020-02-22,79 2020-02-23,150 2020-02-24,227 2020-02-25,320 2020-02-26,445 2020-02-27,650 2020-02-28,888 2020-02-29,1128 2020-03-01,1694 2020-03-02,2036 2020-03-03,2502 2020-03-04,3089 2020-03-05,3858 2020-03-06,4636 2020-03-07,5883 2020-03-08,7375 2020-03-09,9172 2020-03-10,10149 2020-03-11,12462 2020-03-12,15113 2020-03-13,17660 2020-03-14,21157 Edit: for comparison, US data is below. date,cases 2020-02-26,15 2020-02-27,15 2020-02-28,19 2020-02-29,24 2020-03-01,42 2020-03-02,57 2020-03-03,85 2020-03-04,111 2020-03-05,175 2020-03-06,252 2020-03-07,352 2020-03-08,495 2020-03-09,643 2020-03-10,911 2020-03-11,1182 2020-03-12,1577 2020-03-13,2184 2020-03-14,2628

maxerickson 7y ago
A possible explanation is that their testing can't keep up with the spread. ~13,000 test per day for the last several days, with more positive results yesterday for the same number of tests.
- throwaway_pdp09 7y ago
  If true that would apply much more to the US data, where I understand the amount of testing has been extremely low. In any case the data is surely of confirmed cases, so these have got past the testing, no? And I'm not sure if that would produce a flatter-than-exponential curve, which seems to be what it is.

jorisw 7y ago

Justin Fox is a Bloomberg Opinion columnist covering business. A total layman on the subject matter. Stop writing about corona if you’re not an expert. Stop reading and sharing non-expert opinions.