Wednesday, April 1, 2020

Wuhan Virus and Numbers - Calm Down

Today I want to try and talk you into calming down.  Don't believe everything you read or hear, even if it's provided by 'experts.'  As a reminder, my expertise is in physics and electrical engineering.  I did numerical modeling for both my MS and PhD.  I am not a physician, virologist, or epidemiologist.  Nor am I a statistician.

But let's start with an example of why you should not trust what you here.  First, the Surgeon General is still insisting that masks won't help.  Dr. Fauci and others are coming around.  But this one is just common sense.  The virus is spread through coughing and exhalation.  Masks reduce the force and volume of air that gets past the mask.  They also reduce the number of particles or airborne particulates, including viruses, that are propelled away from your face.  Less force/kinetic energy and less particles mean less chance of spreading anything.  Acting in reverse, a worn mask is going to cut down 'stuff' that gets into your airways.  The WHO, the CDC, and the Surgeon General all lied to your faces about masks not helping.

Now let's turn to a 'simple' number thought experiment.  The CDC and everyone else says wash your hands for 20 seconds to get rid of the virus on your hands and reduce the chance of spreading.  Now how do you suppose they came up with that number of 20 seconds?  Do you suppose they spread COVID-19 virus on tables, had everyone smear their hands, do a few handshakes, then had groups of 100 people wash for 5, 10, 15, 20, 25 and 30 seconds, then tested the amount of virus on their hands?  No way.  I can pretty much assure you no people were involved with any testing of live COVID-19 and hand washing.

They may have done some test tube experiments with soap and water to see how long it took to degrade the virus.  They probably extrapolated from some previous tests with non-lethal virus-like entities.  They probably also did a few modeling experiments.  My guess is they came up with the number that 10 seconds almost always was enough to get rid of viruses in their 'experiments.' 

No engineer (or scientist) is going to go with the figure that their calculations show is correct when safety is involved.  They are going to throw in a fudge factor.  So if you are building a bridge, you throw in a factor of 3 to 10 in terms of strength in case your calculations are off or you have an unexpected event.  I cannot imagine for a pandemic, that they didn't throw in a fudge factor.  So my guess is 10 seconds was considered safe, and they put out 20 seconds.

Now, like the virologists, I will wash my hands as close to 20 seconds as I can.  I just know that if I'm accidentally short, the chances of not getting rid of the virus is still pretty good.

Now comes the important numbers.  Curves were presented that show a range of 100,000 to 220,000 deaths in the US from COVID-19.  I think that was cumulative deaths (area under the curve) rather than instantaneous deaths.  Now how do you suppose they get those numbers?  Dr. Birx says modeling and they both claim that the models/averages include New York numbers.  New York city and to some extent New Jersey (in one big metropolitan area) have rapidly rising numbers that look like Italy.  The rest of the country, for the most part, have gentle contagion/hospitalization/death curves that look more like South Korea.  The task force were concerned that a handful of cities may become breakout regions like New York.

But what the chart seemed to show was an average/mean curve (most probable) in the middle of the chart with probably three sigma variations (standard deviations) that corresponded to the best and worse case curves.  But they didn't say the best and worst were 3 sigma (confidence level of 99.9%) or 2 sigma (97% confidence) or 1 sigma (84% confidence) or something else.  Even if they did, that just means the data points they used in their calculations spit out the value of a standard deviation.

And the standard deviation goes up if the data point values vary widely.  Having a possible variation of 60,000 deaths from a mean of 160,000 (38%) is a vary broad range.  It tells me the numbers don't mean much.  They are ALL OVER THE PLACE.

Now think about the curve you saw--a rise, peak, then a gradual decrease.  You know that they have not seen that curve anywhere in the US.  So either they are using hypothetical models based on a variety of assumptions, or they are using data from elsewhere in the world with COVID-19.

But you saw China's data rise, peak, then stop.  No gradual decrease.  Of course, nobody believes their numbers anyway.  Italy is still near the peak, and most European nations are still on the rise part.  South Korea and Japan are maybe in the gradual decrease.  But do you have any confidence they did a good job of testing broadly?  And do you want to assume that nations using 100% masks are going to be representative of what we see here in the US?  Which of those countries did they base their curve on?

Maybe they just used a simple model for all viruses with a rise, peak and gradual tail?  And then did variations based upon the contagion value (R, how many people each infected person spreads the virus to).  But who can measure the R value when different parts of our population are packed in differently and behave differently?

So it's all a guess.  I can build you a numerical model that will give you any number you want.  And I can defend it too.  But simple logic is probably just as easy in this case.  The Wuhan virus is more contagious than the flu and a portion of the infected group die at higher rates (the elderly and sick).  So if the flue kills 25,000 to 60,000 people in the US annually, the COVID-19 virus is going to kill more than that.

But we don't do social distancing and close our economy down for the flu.  That mitigation is going to have a lot of effect.  Then too, how effective will treatments such as hydroxychloroquine be?  We don't know.  Do you think it will be as effective as the flu vaccine is in mitigating the effects of the flu?

Finally, I think it was Dr. Birx, or maybe Dr. Fauci, that said the old 2.2 million death prediction depended on 3 waves of COVID-19 over three years.  And that was a worst case result with no mitigation.

Yesterday, they didn't mention any 3 waves, and I sure don't see any 3 waves in the curves.  That suggests some kind of modeling disconnect with what they presented.  Didn't they want to show the 3 waves?  Did they assume a vaccine would be ready before wave 2 so the numbers for the 2nd and 3rd wave would fall below the numbers for the flu?  Or have they manipulated the data?

So here are my take aways.  The numbers are BS.  Sure, they represent the output from some model.  But I have no reason to trust the numbers, either the input or the output.  Sure, they are big enough to scare everyone into keeping the economy closed for another 30 days.  But beyond that, why should I believe them?  I do not.  They are guessing, and guessing numbers that are high enough to scare, but low enough so people don't riot in the streets. 

Instead of worrying about those numbers, go on about whatever life the government is allowing you.  Enjoy it.  Stay as safe as possible.  Then watch the US statistics and events and see what happens.

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