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Sunday, March 22, 2020

How To Fight Covid-19

I found via FR a very info rich powerpoint developed by Michael Lin of Stanford University. What I've done is presented pp. 13-19 below. The whole is longer and, as I said, info rich/dense. You can find it here.

I've edited the pages I've selected, taking out references and some of the calculations. Anyone who thinks I misrepresent things is free to check the original. On the last page re medications, I've simply used the heading. The pages I've selected--the full powerpoint presentation has a total of 37--are the ones that I believe will be most informative for most readers, but if you go to the original you'll find additional information on how Covid-19 kills, etc.

As you'll see, as I've been arguing, Lin believes the US is still early in the process--which gives us hope. OTOH, pandemics like this can develop and get out of control rapidly. You'll see below that Lin crunches the numbers and figures that this may not peak in the US until May - June, but that we need to act by, well, right now. The period March 16 to April 16 will be critical in Lin's estimation. 

That's the bad news, but the good news is that that's what will happen if we do nothing. We're already doing something, and Lin's estimates give us a metric by which to measure--are we doing enough?

Is it possible that Lin is off in his estimates? Yes. Why, then, is this important? Because this is probably very close to the type of presentations President Trump and others are receiving and on which they are basing their policy decisions. If public official's appear to be freaking out--this is why. Trump will have in mind the time frame that Lin outlines in formulating his policies. If Lin and others are right, the worst is well ahead of us, but we can try to mitigate it. Read this, and you'll have some idea why public officials are doing what they're doing from a medical standpoint. You already know why they're doing what they're doing in the stock market.


We are still early in the process


What should we do when 1 in 1000 in the Bay Area just got the virus?

About 50% of patients will be asymptomatic, based on experience with the Diamond Princess, an estimate from Wuhan data, and an estimate from passengers on evacuation flights.

Average incubation period is ~7 days. Transmission may begin 2 days before symptoms, so on average at 5 days after infection.

Thus the 1 in 1000 who just got the virus this week will start spreading virus and then develop symptoms over the next week (obviously not synchronized but continuously over time).

We can protect ourselves against any undetected spreaders by keeping our hands and common surfaces clean, and maintaining distance when we talk (and use of face masks if you’d like).

Risk is 1/1000 from direct personal contact; higher from touching fomites [surfaces capable of carrying infectious organisms] in proportion to the number of people touching them between cleanings.

• Take action to reduce a currently low risk of acquiring/transmitting the virus to as low as possible.

3/20/20 Michael Lin, PhD-MD 13

How bad could this be?


If we did nothing and doubling rate remains 1 week, then in worst case, deaths and infections will grow exponentially until virus runs out of people to infect (using CA-only numbers now).

• For US numbers, multiply by 8: ~2M (million) cumulative deaths.

• This is not meant to be numerically accurate, it’s just for illustration, but it fits well the worst-case scenario by an authority in disease modeling.

Compare to Spanish flu of 1917-1918: Cumulative infection rate 27%, IFR 2%. Spanish flu might have higher IFR than COVID-19, but medical care was much worse then (no ventilators, no drugs). In reality COVID-19 is likely the more severe disease. In any case, Spanish flu was devastating.

3/20/20 Michael Lin, PhD-MD 14

Estimated 5% of total infected (not diagnosed cases) require hospitalization and 2.5% require ICU. Average hospital stay is 3 weeks, and starts 2 weeks after infection (1 week after diagnosis).

• Wuhan numbers are 15%/5% of cases, but that is with smoking (60% of males) and pollution (everyone), also infection rate underdetected by 50%.

Biggest infection surge occurs in the weeks of 5/15, 5/22, and 5/29, when 10%, 20%, and 20% of population = 32M, 64M, and 64M get infected. This will result in 1.6M, 3.2M, and 3.2M needing hospitalization starting 6/7, 6/13, and 6/20. As patients need to stay ~3 weeks, 8M will overlap on the week starting 6/20.

[My rough table]:
Big surge:            5/15, 5/22,  5/29
% infected:          10%,  20%,  20%
# infected:           32M,  64M,  64M
Need Hospital:      1.6M, 3.2M, 3.2M
Date to Hospital:   6/7,  6/13, 6/20

– <1m beds="" hospital="" in="" p="" us.="">– So we must slow down doubling time from 1 week to ~8 weeks, so hospitalizations peak at at <1m .="" b=""> 
<1m beds="" hospital="" in="" p="" us.="">
<1m beds="" hospital="" in="" p="" us.=""><1m .="" p="">3/20/20 Michael Lin, PhD-MD 15


We need to ‘flatten the curve’ now


The next month is critical: March 16 to April 16. We must do whatever we can to reduce R0 or increase doubling time. It will take several weeks to know if it’s working.

If we are still doubling each week on April 16, we have only another month to get a second chance.

If that doesn’t work by May 16, there will be no third chance.
We would have to immediately clamp down to avoid hospital overflow. This would require Wuhan-like measures such as central quarantine for sick and enforced home-isolation for everyone else.

3/20/20 Michael Lin, PhD-MD 16

What can flatten the curve?


Weather: Maybe 10 oF increases the doubling time 2x
Goal is to reduce the reproductive number R0 (how many people infected by each patient).

– Current R0 rate ~ 2 (one person infects 2 others. If they do this in 7 days, it explains doubling time of 1 week).
– Drop R0 to 1.5: Doubling time would increase ~2-fold.
– Drop R0 to 1.25: Doubling time would increase ~4-fold.
– Drop R0 to 1.125: Doubling time would increase ~8-fold.
– Drop R0 to 1.0: Doubling time would become infinite (constant rate of new cases).

Social distancing, wide testing and tracing, and strict hygiene (face masks, hand sanitizer): This is the approach in SK, Taiwan, Singapore, HK. This seems to have dropped R0 to 1.0 (constant rate of new cases).

Complete household isolation, immediate quarantining of symptomatic, strict hygiene: This was the approach in Wuhan. R0 dropped from 3.9 to 0.32.

Is presymptomatic or asymptomatic transmission a factor? Yes, but how much is unclear.

In Wuhan, R0 fell from 1.3 when symptomatic patients stayed at home to 0.32 when they were centrally quarantined. This suggests only 24% of transmission events occurred before symptoms. But another study estimates 44% of transmission is in presymptomatic period.
– How about asymptomatics? Undiagnosed carriers estimated to be ~55% as infectious as diagnosed cases. As undiagnosed carriers are more likely asymptomatic than diagnosed cases, this suggests asymptomatics are not as infectious as symptomatics.

3/20/20 Michael Lin, PhD-MD 17

It’s not easy, but social distancing, fast testing, and immediate quarantining can be enough!


3/20/20 Michael Lin, PhD-MD 18

Thanks to earlier research, we already have drugs with activity against the virus


3/20/20 Michael Lin, PhD-MD 19


13 comments:

  1. Dr Lin saved the best for last, where he explained how the CDC /FDA are incompetent. China CCP is actually mass-producing Chloroquine, while American CDC/FDA have actually blocked it because of turf battles. No surprise to anyone experienced with our government of petty-tyrants and unaccountable-incompetents.

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    1. Yes. Actually that aspect was highlighted in the post at FR where I found this, but I guess I just kinda took that for granted. OTOH, I assume that a guy with his background is probably very liberal, so that may have been a bit of an awakening for him.

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  2. Good news in testing!

    Nationwide 250,000+ tests done. Nice improvement.
    https://covidtracking.com/data/

    Hat tip powerline:
    https://www.powerlineblog.com/archives/2020/03/rapid-progress-on-covid-testing.php
    Showing the increase in us tests done.

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  3. Dr. Lin thought Trump has not done a great job per the pdf, and he should have let Dr. Fauci run the briefings.

    I agree with his comments in the incompetence of the FDA and CDC, it’s worse than I thought. I did not realize the original cdc test was based on 30 year old technology. I had read it could only be run on one machine, and the cdc was very secretive about details on that machine. And another article mentioned an fda inspector was denied entry for a day, and then found contamination issues.

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    1. Ah, thanks for that info. In response to aNanyMouse I had wanted to say that Trump had mentioned the inadequacy of our test, but I wasn't sure. Now I'd bet that's where I heard it.

      Medical/Science people are always biased in favor of their own kind, but the proof is in the pudding. Lin is talking out of both corners of his mouth. OTOH, CDC is criminally incompetent, OTOH Fauci should be the one doing the briefings. Don't work that way. The buck stops on Trump's desk. If it stopped on Fauci's desk he'd be out on his ass by now.

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    2. I wonder if DJT, or any in the MSM, ever referred to (let alone stressed) a major new study of test accuracy, pub. on 5 March, in the Chinese journal Zhonghua liu, see
      https://pubmed.ncbi.nlm.NIH.gov/32133832/ :
      "Potential False-Positive Rate Among the 'Asymptomatic Infected Individuals' in Close Contacts of COVID-19 Patients"

      From the abstract:
      "Results: When the infection rate of the close contacts, and the sensitivity and specificity of reported results were taken as the point estimates, the *positive predictive* value of the active screening was only 19.67%, in contrast, the *false-positive* rate of positive results was 80.33%.
      The multivariate-probabilistic sensitivity analysis results supported the base-case findings, with a 75% probability for the false-positive rate of positive results over 47%."

      I quite doubt, that the MSM has told us, that we should doubt *47%* of these tests' results.

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    3. I believe that DJT did allude to that. I seem to recall that when he said we'd be getting a greater testing capability the test used would also be more accurate. Can't swear to that, but it's my recollection for now. That's part of why a serum test would be helpful.

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  4. "What should we do when 1 in 1000 in the Bay Area just got the virus?

    Again, it isn't the case that only 1 in a 1000, or whatever the confirmed cases number shows: Whatever the confirmed cases number is, multiply it by at least 10, and probably 100

    As I have pointed out over and over- pretty much everywhere the percentage of positive tests is between 8 and 13%- in the first 100 tests, the next 1000 tests, and the next 10,000 tests. If San Francisco is showing a low number of cases, then it means that a low number of people with flu-like symptoms are getting the test run. I can't emphasize this enough.

    Here is what is happpening everywhere. Someone eventually tests positive in an area. At first, this isn't concerning- it is one positive case, but then a second one is found in contact tracing. At that point, the people in the area, let's say, a 20 mile radius start to wonder if their flu-like symptoms is coronavirus. So, they start wanting to be tested. The next day twice as many people get tested, and the positives double; this causes more people to want to be tested, and so on. Eventually you get the full blown panic that we are seeing in New York right now where everyone with flu-like symptoms wants a test, and since about 10% of the people with flu-like symptoms have coronavirus all along, then the new cases explode.

    This has ancilliary effects- as the panic deepens, people start to worry that there won't be a hospital bed for them or their parents if their symptoms worsen- they start to pressure doctors to admit themselves or their relatives so that they aren't shit out luck a week later. The precautionary principle is causing doctors to admit people who shouldn't be in the hospital for the symptoms they have. So, we end up with the hospitals overrun with COVID-19 positive people, and then the shit hits the fan- the other patients, much sicker with other life-threatening illnesses are infected and start dying. Many of the doctors, nurses, and orderlies get infected and there is no way back from the disaster.

    The above is what happened in Italy- the hospitals became overrun with COVID-19 sufferers who could have been treated at home, and all protocols for isolation broke down. Additionally, the nursing homes did nothing to protect their patients from visitors and infected staff who got infected at the hospitals and clinics. So those elderly patients started to die.

    Here in Tennessee, as of this morning, we had about 280 (is higher this evening) confirmed cases, and had run about 3000 tests at that point- the typical ratio of positive results that I see in state after state that actually reports total tests run. The people here just assume that means 280 cases statewide. This is wrong- if Tennessee had run 100,000 tests the last week, the new cases would have been around 10,000- it is just that the panic to get tested hasn't set in yet, but it is starting to, and I expect the tests run in Tennessee start the same escalation they saw in New York starting last weekend. This will happen everywhere, but it isn'because the disease is spreading rapidly, it is because the testing is spreading rapidly because the panic is spreading rapidly.

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    1. Suggestion: Why not read before commenting. If you think Lin doesn't understand the reality of what lies behind the confirmed cases numbers then you simply haven't read what he says.

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    2. I did read it before commenting- he doesn't get it either- he is still locked into the belief that the numbers of infected are low enough that certain damaging policies can arrest it enough. We are way past that point, and probably have been since January.

      What has changed is the panic response. We are going to end up with economic catastrophe caused by doing things that will littl to no effect on the outcome of the disease's progress.

      You can't lock the country down for 10-12 weeks. You will have 50% unemployment at a minimum afterwards, if not 75%. Right now, on this path, we are just a couple of weeks away from all the food disappearing from the grocery stores and the distribution pipeline. It will happen so fast we will be stunned by it.

      This idea that we can run the country on a skeleton staff for 3 months or more is the most idiotic thing I have ever read. We are going to end up killing 10 times the people the virus would have at its worst.

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    3. "we are just a couple of weeks away from all the food disappearing from the grocery stores and the distribution pipeline. It will happen so fast we will be stunned by it."

      You're right--I will be stunned by it. And when it happens I'll write a post titled "Yancey told me so," then curl up in a corner and die.

      In the meantime I recommend you read the Rebecca Grant article which offers the historical experience of the Spanish flu to contradict everything you're claiming.

      Why should I take your argument seriously when you refuse to take historical experience seriously--you refuse to even consider it or take it into account in your comments.

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  5. In my opinion, this can't be stopped by any action we take now- I think the diseased has numbered in the millions already since February, and we are just now testing enough people to reveal it however modestly we have done so far.

    You want an estimate of how many? I would say it is 10% of the people with flu-like symptoms (fever, sore throat are the requirments right now). How many people typically have such symptoms any give day in March? Well, since the flu seems to infect about 50-100 million people a year, all strains, then on any given day of a year, you should expect about a 1-2 million have such symptoms at any day, and in March, probably 2-3 million. So, right now, there are probably 200,000-300,000 infected people. There were probably 200,000-300,000 of them two weeks ago, but a different 200k-300k. Same 4 weeks ago when testing got started in the US.

    I don't know how to turn off the panic that overruns the hospitals, but you could minimize the impact by dedicating entire facilities to COVID-19 patients and the personnel so that every other patient has a minimized risk of getting infected and dying.

    However, instead of that, we waste our time with lockdowns of dubious value.

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  6. A shrewd Jewess asks some key questions, about the numbers commonly presented about this disease, see
    https://www.theNewNeo.com/2020/03/23/epidemiologists-as-the-new-gurus-what-about-the-excess-death-rate/ :

    … to know the all-important case fatality rate of this disease, we have to know the numbers of people infected. As we test more and more of the population, we learn more about that, but not even remotely as much as we need to know.
    And unless we test the entire population, including those with no symptoms, and do it at intervals, we can’t know in real time or perhaps ever.
    But we do know another important number: how many people have died so far of COVID-19. Or do we? Is everyone who dies of any respiratory disease, being tested for the presence of the virus?
    And if they are all being tested, do we know that those with a positive COVID-19 test *actually died from the virus*, and not from some other condition they might have? That sort of thing has been described as taking place in Italy, for example:

    (she quotes from https://www.Telegraph.co.uk/global-health/science-and-disease/have-many-coronavirus-patients-died-italy/?fbclid=IwAR0QkEmrIJHo575gU86SUiUpntWD3wD0xoJlnzZ34Ebs8uKmh_jqlNgVnrw )

    …Prof Ricciardi added, that Italy’s death rate may also appear high, because of *how doctors record* fatalities.
    “The way in which we code deaths in our country is very generous, in the sense that all the people who die in hospitals WITH the coronavirus are deemed to be dying OF the coronavirus.
    “On re-evaluation by the National Institute of Health, only **12 per cent** of death certificates have shown a direct causality from coronavirus, while **88 per cent** of patients who have died have at least one pre-morbidity – many had two or three,” he says.
    This does not mean that Covid-19 did not *contribute* to a patient’s death, rather it demonstrates that Italy’s fatality toll has surged, as a large proportion of patients have underlying health conditions.
    (end quote)

    To understand the meaning of all the deaths in Italy, it would be extraordinarily helpful to know one figure that I’ve never seen discussed: the number of *excess deaths*; that is, the number over and above *what is usual* this time of year in Italy.
    I have no doubt the number is higher than usual, and that there are excess deaths, particularly in certain regions of the north, where the virus has been concentrated. But *how much* higher? Italy *ordinarily has a particularly high rate* of death from the flu, which makes the “excess death” figure especially important to know.
    Are significant numbers of the deaths we’re seeing in Italy, deaths that would be taking place anyway, from the flu or other illnesses we’re accustomed to? And if so, how many?...

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