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thenginer
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Coronavirus (COVID-19) Thread

23 Mar 2020 06:24

I'm under total quarantine in a student dorm in poland 
Can't live my room :S
 
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midtskogen
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Coronavirus (COVID-19) Thread

25 Mar 2020 13:22

Watsisname wrote:
Source of the post The virus does not have some intrinsic transmission coefficient or mortality rate. Both depend on how we respond to it.

This is important.  When all this is over, the mortality will say less about the virus itself than it will tell how well we are able to protect the vulnerable.  Complete lockdowns and travel restrictions will help, but in an indirect way.  Isolation of the vulnerable is more direct and may be more effective at a much lower cost.  I think the right approach is to be pragmatic about restrictions for low risk people, but very strict when it comes to isolating the vulnerable.
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Coronavirus (COVID-19) Thread

26 Mar 2020 00:28

midtskogen wrote:
Watsisname wrote:
Source of the post The virus does not have some intrinsic transmission coefficient or mortality rate. Both depend on how we respond to it.

This is important.  When all this is over, the mortality will say less about the virus itself than it will tell how well we are able to protect the vulnerable.  Complete lockdowns and travel restrictions will help, but in an indirect way.  Isolation of the vulnerable is more direct and may be more effective at a much lower cost.  I think the right approach is to be pragmatic about restrictions for low risk people, but very strict when it comes to isolating the vulnerable.

Right now the complete lockdown has helped (slightly).  We went from 5,200 new cases the other day to 4,700 new cases yesterday.  The hospitalization rate also went down a bit, from doubling every other day to now doubling every 4.7 days.  Still too early to tell if this will continue, and the peak is predicted to be in 21 days here.
Cuomo the governor is right, instead of deploying the ventilators and other equipment simultaneous everywhere and diluting its effectiveness it should first be sent to the hot spots and then we'll pass it on to the next hot spot, etc.  The curve doesn't simultaneously peak everywhere.
 
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Coronavirus (COVID-19) Thread

26 Mar 2020 00:35

Stellarator wrote:
midtskogen wrote:
A-L-E-X wrote:
Source of the post give everyone $1,000 to stimulate the economy after this horror ends. A $1 trillion stimulus package

From where?  Tax increases?  Borrow from China?  Banknote printing?

Generally speaking, these emergency funds are from governmental contingencies established prior for these situations, or set-up during the onset. Most Western countries are now implementing these. While most do not apply to *every* citizen, a greater concern is simply how long these would last and just how effective they are at alleviating financial burdens.

Did Canada just agree to pay its residents $2,000 a month for four months?  Nice.
 
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Coronavirus (COVID-19) Thread

26 Mar 2020 03:28

I am so happy with Washington State's response. To the rest of the US, you can do this!

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Graphic by Getreuer on wikipedia
 
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Coronavirus (COVID-19) Thread

26 Mar 2020 04:35

As mentioned before, it may be worth looking at Norway and Sweden which have chosen different strategies.  Norway chose "the hammer" shutting down just about everything, whilst Sweden chose to keep most things running focusing on isolating the vulnerable.  Sweden in blue and Norway in pink below.  The testing methodology might differ and Sweden has almost twice the population, but it's the shape of the curves that matters most.

I think Tomas Pueyo's "flattening the curve" message in his "Why You Must Act Now" was good, but the "hammer" message in his follow-up is likely to be wrong or at least exaggerated or not very nuanced, i.e. that R must be kept below 1.  We can probably do fine with an R slightly above 1.  The main real effect of the hammer is to make the restrictions that remain after the most severe have been lifted, more acceptable to the public. However, if only the long term restrictions and general caution had been in effect from the beginning, the result would be more or less the same bit not economically. As long as the healthcare system is at top of the problem, the hammer will make more harm than good and an early hammer does not seem to be required to keep things under control.

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Coronavirus (COVID-19) Thread

26 Mar 2020 05:18

"I'm sure the universe is full of intelligent life. It's just been too intelligent to come here."
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Coronavirus (COVID-19) Thread

27 Mar 2020 02:18

midtskogen wrote:
As mentioned before, it may be worth looking at Norway and Sweden which have chosen different strategies.  Norway chose "the hammer" shutting down just about everything, whilst Sweden chose to keep most things running focusing on isolating the vulnerable.  Sweden in blue and Norway in pink below.  The testing methodology might differ and Sweden has almost twice the population, but it's the shape of the curves that matters most.

I think Tomas Pueyo's "flattening the curve" message in his "Why You Must Act Now" was good, but the "hammer" message in his follow-up is likely to be wrong or at least exaggerated or not very nuanced, i.e. that R must be kept below 1.  We can probably do fine with an R slightly above 1.  The main real effect of the hammer is to make the restrictions that remain after the most severe have been lifted, more acceptable to the public. However, if only the long term restrictions and general caution had been in effect from the beginning, the result would be more or less the same bit not economically. As long as the healthcare system is at top of the problem, the hammer will make more harm than good and an early hammer does not seem to be required to keep things under control.

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Sweden's response seems to be more like South Korea's.
Bad news from here, 100 people died yesterday alone, including 13 people at Elmhurst hospital, which is 5 miles from me.  Doctors and nurses are wearing trash bags because they lack protective equipment.  I am not leaving my house at all, except to get food.  Roads are set to be shut down starting tomorrow.  We seem to be getting 5,000 new cases every day and we now have 40,000 cases and 400 deaths.
Developing an antigen test to identify who has resolved (even if asymptomatic) and who may perhaps now have immunity as well as an at home test for the virus (which still has to be sent in to a lab.)
 
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Coronavirus (COVID-19) Thread

27 Mar 2020 07:32

Prime Minister of the UK Boris Johnson has recently tested positive for the coronavirus. He is now self isolating, but he only has mild symptoms. Meanwhile, the USA beats China for most confirmed cases (85,500 positive).
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27 Mar 2020 17:15

 
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Coronavirus (COVID-19) Thread

28 Mar 2020 02:24

Pretty interesting.  Testing in Iceland, however, indicates that as many as 50% of those infected have no or hardly any symptoms.  If the models had been run in such a configuration, I wonder how the results would change.  And one thing these simulations miss is the mortality distribution across the population.  If a disease is perfectly harmless for people under, say, 70, and mortality is very high for those above, then, if the disease has already spread, effective isolation of the vulnerable while the rest quickly become "recovered" would be very effective.

An interesting point was also that travel restrictions at this point may have limited effect.  But the effect of avoiding hubs is large and public transport acts like a hub.  For international air travel an hour or more in lines through immigration and emigration is not uncommon (and probably a far greater risk for getting infected than during the flight itself), and ironically, during times of epidemics, border control is much stricter and these lines become worse.
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Coronavirus (COVID-19) Thread

29 Mar 2020 00:23

midtskogen wrote:
Source of the post Pretty interesting.  Testing in Iceland, however, indicates that as many as 50% of those infected have no or hardly any symptoms.  If the models had been run in such a configuration, I wonder how the results would change.

I think we can gain some intuition by looking at the models he runs starting at 6:39, which show the effect of changing the fraction of cases that are quarantined (e.g. because they show no or weak symptoms and don't get tested). In this model, 100% of cases being quarantined is very effective at stopping new infections, while if 80% are quarantined then the curve is flattened but with a long tail, resulting in twice as many total cases.

So having some fraction of cases not being detected and quarantined causes a disproportionately greater number of people catching the virus. If about 50% of cases are nearly asymptomatic and not known, then measures to slow the spread by identifying and quarantining infected by symptoms are dramatically less effective (see for example the simulation with communities at 50% quarantine at 8:35 -- it's only barely better than if no action was taken at all!) This goes with his insight that it is not the diseases that have the highest mortality rates that are the most dangerous to the world. It is the ones that are lethal to some, but weakly symptomatic or even asymptomatic in others, which makes it more difficult to track and contain its spread.

How to solve this problem? The most obvious solution is to test everybody. But in many countries this is not so easy because testing supplies are limited. The rate of testing capability must increase faster than the rate of new cases.

Another way is through contact tracing. If we can trace back every person a confirmed infected person was in touch with, such as through cell phone data, and get those contacts to all self quarantine, then that dramatically helps to slow the spread because we catch many more people before they develop symptoms, or even if they would not show symptoms but still spread it. This is how Singapore acted, and now they're wanting to make the technology more widely available. I can easily imagine a lot of people not wanting to use such measures for fear of invasion of privacy, but I think for the amount of good it can do it would be a wise option. Perhaps the fears could also be culled somewhat by ensuring oversight by an independent organization, and that the use of the technology goes away once the pandemic ends.

midtskogen wrote:
Source of the post And one thing these simulations miss is the mortality distribution across the population.  If a disease is perfectly harmless for people under, say, 70, and mortality is very high for those above, then, if the disease has already spread, effective isolation of the vulnerable while the rest quickly become "recovered" would be very effective.

I find this very sensible, though I also fear a few potential problems when applied to the real situation.

First is the size and complexity of the vulnerable population. It seems quite clear that mortality rates increase dramatically at higher ages, so it is paramount to protect them the most. But it is also not simply zero below the age of 70, or even 50. As we've seen, the mortality rate in all age groups is about 20 times higher than the seasonal flu, and under the age of 30 it amounts to about 1 in 500 cases.

Now we may expect the true mortality rate is less than that because the fraction of people in those ages who show symptoms and get tested is also smaller, but I don't think it can be much less. I could believe a factor of 2 or so, but probably not a factor of 10, and that also doesn't seem to be borne out much from the data we're seeing from outbreaks in cruise ships or other areas where testing is more robust.

Add to this the effect of people with other health problems that increase their risk such as asthma, diabetes, and hypertension. So it's really a large number of people across a broader spectrum than age that will want to avoid getting this virus at all, and I worry that if we tried to protect these who are most at risk while letting the virus spread through the rest of the population, it could prove more difficult and we may still see an alarming number of deaths. I very much hope I'm wrong, but I wouldn't want to gamble lives on it.

My second concern is that if the virus is allowed to spread through much of the population quickly, there are that many more chances for a new strain to diverge which is more lethal to different age groups, complicating mitigation efforts further. We know that this is not impossible. In fact it happened in the 1918 pandemic, where the second wave of infections was far more deadly, especially to those aged 20 to 40. That was perhaps an unfortunate case of artificial selection, where the soldiers at war who had the milder strain stayed on the battlefield, while those with the deadlier strain were sent home, enabling it to spread further.

SARS-CoV-2 is a new virus in humans, and we're learning more about it, and how to best respond to it, very rapidly. My hope above all else is that we can minimize the amount of deaths without hurting economies too much in the process, and I do not see these goals as mutually exclusive.
 
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Coronavirus (COVID-19) Thread

29 Mar 2020 02:16

Watsisname wrote:
Source of the post If about 50% of cases are nearly asymptomatic and not known, then measures to slow the spread by identifying and quarantining infected by symptoms are dramatically less effective (see for example the simulation with communities at 50% quarantine at 8:35 -- it's only barely better than if no action was taken at all!) This goes with his insight that it is not the diseases that have the highest mortality rates that are the most dangerous to the world. It is the ones that are lethal to some, but weakly symptomatic or even asymptomatic in others, which makes it more difficult to track and contain its spread.

Indeed.  If this is the case, one option is to quarantine just about everybody.  Some countries try this, but it's probably not a good approach.  It's impossible and the consequences are dramatic.  In this situation I think the right approach is to isolate the vulnerable and test their nurses, even if they have no symptoms, as often as possible, and the virus will just have to work through the rest of the population at a pace controlled by pragmatic social distancing.  Cell phone data might be a good tool, with which the effect will be as good as quarantining the entire population but without the effect of shutting down society.  The resolution might be a bit low, but I do think clever algorithms can do useful tracing and reasonable judgements of who should be quarantined.

It's been 2.5 weeks of social distancing over here now, and whilst there still is a steady, non-accellerating increase in infections, health authorities report a dramatic decrease in the percentage of positive flu test, which may be an indication of how effective social distancing can be, and it could even more than offset the number of covid related deaths, but that's far too early to tell.  23 deaths so far (avg age well over 80) and a mortality rate of 0.4% (but likely infections without severe symptoms are not tested except for those working in healthcare).
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A-L-E-X
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Coronavirus (COVID-19) Thread

30 Mar 2020 03:25

Watsisname wrote:
midtskogen wrote:
Source of the post Pretty interesting.  Testing in Iceland, however, indicates that as many as 50% of those infected have no or hardly any symptoms.  If the models had been run in such a configuration, I wonder how the results would change.

I think we can gain some intuition by looking at the models he runs starting at 6:39, which show the effect of changing the fraction of cases that are quarantined (e.g. because they show no or weak symptoms and don't get tested). In this model, 100% of cases being quarantined is very effective at stopping new infections, while if 80% are quarantined then the curve is flattened but with a long tail, resulting in twice as many total cases.

So having some fraction of cases not being detected and quarantined causes a disproportionately greater number of people catching the virus. If about 50% of cases are nearly asymptomatic and not known, then measures to slow the spread by identifying and quarantining infected by symptoms are dramatically less effective (see for example the simulation with communities at 50% quarantine at 8:35 -- it's only barely better than if no action was taken at all!) This goes with his insight that it is not the diseases that have the highest mortality rates that are the most dangerous to the world. It is the ones that are lethal to some, but weakly symptomatic or even asymptomatic in others, which makes it more difficult to track and contain its spread.

How to solve this problem? The most obvious solution is to test everybody. But in many countries this is not so easy because testing supplies are limited. The rate of testing capability must increase faster than the rate of new cases.

Another way is through contact tracing. If we can trace back every person a confirmed infected person was in touch with, such as through cell phone data, and get those contacts to all self quarantine, then that dramatically helps to slow the spread because we catch many more people before they develop symptoms, or even if they would not show symptoms but still spread it. This is how Singapore acted, and now they're wanting to make the technology more widely available. I can easily imagine a lot of people not wanting to use such measures for fear of invasion of privacy, but I think for the amount of good it can do it would be a wise option. Perhaps the fears could also be culled somewhat by ensuring oversight by an independent organization, and that the use of the technology goes away once the pandemic ends.

midtskogen wrote:
Source of the post And one thing these simulations miss is the mortality distribution across the population.  If a disease is perfectly harmless for people under, say, 70, and mortality is very high for those above, then, if the disease has already spread, effective isolation of the vulnerable while the rest quickly become "recovered" would be very effective.

I find this very sensible, though I also fear a few potential problems when applied to the real situation.

First is the size and complexity of the vulnerable population. It seems quite clear that mortality rates increase dramatically at higher ages, so it is paramount to protect them the most. But it is also not simply zero below the age of 70, or even 50. As we've seen, the mortality rate in all age groups is about 20 times higher than the seasonal flu, and under the age of 30 it amounts to about 1 in 500 cases.

Now we may expect the true mortality rate is less than that because the fraction of people in those ages who show symptoms and get tested is also smaller, but I don't think it can be much less. I could believe a factor of 2 or so, but probably not a factor of 10, and that also doesn't seem to be borne out much from the data we're seeing from outbreaks in cruise ships or other areas where testing is more robust.

Add to this the effect of people with other health problems that increase their risk such as asthma, diabetes, and hypertension. So it's really a large number of people across a broader spectrum than age that will want to avoid getting this virus at all, and I worry that if we tried to protect these who are most at risk while letting the virus spread through the rest of the population, it could prove more difficult and we may still see an alarming number of deaths. I very much hope I'm wrong, but I wouldn't want to gamble lives on it.

My second concern is that if the virus is allowed to spread through much of the population quickly, there are that many more chances for a new strain to diverge which is more lethal to different age groups, complicating mitigation efforts further. We know that this is not impossible. In fact it happened in the 1918 pandemic, where the second wave of infections was far more deadly, especially to those aged 20 to 40. That was perhaps an unfortunate case of artificial selection, where the soldiers at war who had the milder strain stayed on the battlefield, while those with the deadlier strain were sent home, enabling it to spread further.

SARS-CoV-2 is a new virus in humans, and we're learning more about it, and how to best respond to it, very rapidly. My hope above all else is that we can minimize the amount of deaths without hurting economies too much in the process, and I do not see these goals as mutually exclusive.

I want all people tested also.  I see a new test is being developed and shipped which will allow for 15 min testing at home.  That would greatly facilitate this.  Why is this being called SARS 2?

Bad news is we've seen the rate of lethality rise up from 1% to nearly 2% here.
Last edited by A-L-E-X on 30 Mar 2020 03:30, edited 1 time in total.
 
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Coronavirus (COVID-19) Thread

30 Mar 2020 03:28

midtskogen wrote:
Pretty interesting.  Testing in Iceland, however, indicates that as many as 50% of those infected have no or hardly any symptoms.  If the models had been run in such a configuration, I wonder how the results would change.  And one thing these simulations miss is the mortality distribution across the population.  If a disease is perfectly harmless for people under, say, 70, and mortality is very high for those above, then, if the disease has already spread, effective isolation of the vulnerable while the rest quickly become "recovered" would be very effective.

An interesting point was also that travel restrictions at this point may have limited effect.  But the effect of avoiding hubs is large and public transport acts like a hub.  For international air travel an hour or more in lines through immigration and emigration is not uncommon (and probably a far greater risk for getting infected than during the flight itself), and ironically, during times of epidemics, border control is much stricter and these lines become worse.

Problem is we're seeing a lot of younger people here die or have damaged lungs as a result of this.  More underlying conditions here, like diabetes, heart disease and obesity.

Also the phrase needs to be changed from social distancing to physical distancing..... using the term "social distancing" makes no sense and is a ridiculous misnomer in modern society.
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