Monday, December 14, 2020

Coronavirus, by the Numbers, As I See It. Mid December


Coronavirus, by the Numbers, As I See It.  12/15/2020

The number of new cases had been increasing at an accelerated rate.  At the end of September, the new cases per day was 40,000 increasing by around 2% per day.  By the end of October it peaked at 101,000 while growing an average of 4% per day.  In November, the number of daily new cases hit a growth rate of 6% per day for 3 days, on the 7, 8 and 10th, before declining.  On November 20, the number of new cases was first hit 200,000.  December has had 10 out of 14 days over 200,000. The last week averaging 215,000 per day.  The good news the rate of increase for all of December is 2% per day.

This brings the estimated number of active cases to over 4.5 million.

And C-19 is now the #1 killer in the US.  Cancer kills 1,650 a day, but is not communicable.  On Dec 9th, my birthday, Covid killed 3,260. Which was the peak number for the month.  The estimate of 400,000 deaths by inauguration day is no longer hypothetical, but a certainty.  We vectoring to have a higher death count in the USA than the Spanish Flu of 1918 at 675,000.  This assumes the 2,500 number per day till the day the first vaccinated person becomes immune (37 days) then drops to 2,000 per day for 5 months after that for no rational reason other than hope and prayers.   Then a 1,000 new cases per day for the rest of the year. 

The US Population in 1918 is 103 million, less than 1/3 what it is now.  So the overall affect on the psyche of the country will be less.

There is a meme running around about the deadliest days in history.  Galveston Hurricane, 8,000, Antietam 3,600, San Francisco Earthquake 3,000.  Already this list is obsolete.  Insert Dec 9, COVID-19 3,260 between #2 and #3.

On the vaccine front.  Pfizer’s was authorized by the UK at the beginning of the month.  Pfizer’s and Moderna’s was authorized on Dec 12, and first injections started on Dec 14.  They expect to have 40 million doses for the US by year’s end, almost enough for those living in long term health care facilities and health care workers. 

The vaccine requires 2 doses, taken a month apart, to be effective, so when you read the number of doses available, you may have to divide by 2 for calculating how many can be vaccinated.  I’ll use the higher number because that is what the Press uses to avoid confusion.

Between Pfizer and Moderna, they expect to ship 70 million doses a month through the winter.  Priority for those will be the over 65 crowd.  By April it is expected to start vaccination of the general population.  By June that would be enough to fully vaccinate about 190 million Americans. 

“Herd Immunity” requires an estimated 80% of the population.  For the USA, that is 265 Million. 

Dr Fauci, who should have a better idea on the production schedules than I, thinks we will achieve herd immunity by Fall of 2021, and normalized behavior by year’s end.

This is probably not a once and done thing.  Earlier reports said that the vaccine will require yearly boosters.

A note on vaccine effectiveness.  A small amount of immunity will develop about 2 weeks from the first dose, emphasis on the word small.  Full immunity about a week after the second dose.  So from day one, with the exception of test patients, the first immune person will be 37 days from Dec 14, or Jan 20.  The irony that that is inauguration day is not lost to me.  45's supporters will make hay of that coincidence.

It is unknown if the vaccine would keep you from spreading the virus.  That would take more long term testing.  It is only been shown to be 95% effective in keeping the patient from getting it.

There are currently at least 15 other vaccines being tested in the USA.  Status unknown.

There was much in the news about not congregating together during Thanksgiving.  And it seems to have worked.  In 2019, 17 million flew over the holiday, only 7 million in 2020.  While good news, there is no way that many people grouping together cannot have an effect to raise the numbers.  A week after Thanksgiving, the percentage increase per day of new cases started rising again. It had been lowering from 6% at the beginning of November to almost 2% per day.  That turned around the first week of December hitting over 200,000 new cases again on Dec 2.  I cannot explain why the percentage increase went down during the middle of November, and the rise the first of Dec is not explainable with the Thanksgiving holiday either.   To be clear, when I refer to percentage increase per day going down, it still means the number of new cases is going up, just not as fast. In the second week of December the rate of increase was down to 1.5%.  Since there should have been a spike caused by Thanksgiving get togethers, I am interpreting this to mean there is an overall decline in the increases.  And the expected spike is masking what could be a downward trend.  The next week will tell the tale. 

A note on how I am doing the percentage increase per day calculation.  The actual day to day numbers jump all over the place, like -16% then +17%.  Some agencies do not report on weekends, some not on Sunday.  Then there are people that are not sure if they have symptoms, and wait till Monday to be tested, causing a surge in reporting Wed/Thur.   I am averaging the daily increase against the previous 7 days in an attempt to produce a more coherent vector.  I also tried 14 days, but only got slightly better results.

A friend of mine suggested using “inverse harmonic mean”, which I have tried a couple of times, both against the percentage and the raw numbers, but both generated numbers that had no discernible correlation to reality, so I suspect I am not doing it right.  If there is any expertise out there interested in giving it a go, please call me.

At the beginning of the month, it was announced that Montgomery County, Pennsylvania, my home town, had reached 85% of its ICU capacity for C-19 patients (48 beds left).  Montgomery County has been one of the wealthiest counties in the nation for over a hundred years and has a lot of hospitals.  A number of new ones have been built in recent years.  So I shudder for less opulent communities of this nation.  Like Lehigh Valley (not an impoverished county by any means), is at 97% with 5 beds remaining.

The hospitalization rate for C-19 hit 100,000 in early December.  109,000 on Dec 13.  About 20% of them in the ICU, and 7% on ventilators.

https://covidtracking.com/data/national/hospitalization

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