[Cris Alarcon]
As test results come in from El Dorado County residents we see a disturbing trend that indicates 6,000 local residents will test positive for COVID-19 and from 20 to 60 residents of those with die from complications caused from the virus.
Externally we see leaders from President Trump to the bitterly divided Congress members taking very significant measures to stop the spread of this deadly virus.
The county has confirmed 18 cases of local residents.
Less than 800 people in our county have been tested.
614 tests have verified results.
In El Dorado County 3% of verified tests are positive results of being infected by COVID-19.
In the age range of 44-65 the mortality rate is 1%-3% in developed countries like Italy and Spain, as well as New Your state.
51% of El Dorado County residents are 50-years-old or older.
There are significant known unknowns in the statistical analysis that greatly affect the Margin Of Error in the calculations made below that lead to a number of 20-60 expected deaths in our county residents.
I will detail the calculations made as well as the margin of error factors.
Numbers in our county. 18 people of <800 tests. I will note these as “P”
Number of total verified test results [Neg = 596, Pos = 18 for a total pool of verified test results is 614. I will call this “B” for Base pool.
With a Base of 614 positive verified results, and 18 verified positive to find the Positive percentage of tested we use this calculation,
B / P = gross number that is then divided by 100 to get the Percentage of those that resulted in verified positive results to all verified test results.
Math = P/B/100 or 18 /614/100 = 2.93... or rounded to 3%
3% of verified tests in El Dorado County have resulted in Positive results.
This is test results for 614 residents in our county of 200,000 residents. If we take this 3% rate of verified tests of 614 residents and extend it to the full population we find that 6,000 residents will test positive for COVOD-19.
Math = 200,000 X 3% [.03] = 6,000.
Then we apply the mortality rate seen in New York State for 45-65-year-old patients is 1.49%. We can anticipate that out of our county residents with this virus will cause 89 deaths. [NY stats range from a mortality rate range of .015% and for under 18-year-old to a rate of 11.3% for those 75-year-old and older.
I used a mortality rate that represents the average age of El DOrado County residents, 1.48%.
Math = 6,000 X 1.49% [.0148] = 89.
Margin of error from a small sample size. Without 100% of the population included there is always a margin of error expressed as a ‘+/-” number included with estimates.
Math = [shortened - Size of population total (200,000) with 96% confidence level with only 614 sample size is a margin of error of +/- 3% or for 89 it is “89 +/- 3 people - or 86 to 92]
There are other claims that would affect this number, like claims of underreporting. These are unknown so I stuck with known hard numbers.
The hard number that greatly affects the predicted number of deaths is the effect that “Social Distancing” has on the infection rate spread.
Many examples of the effectiveness in this variable are seen from China, to Italy, to New York this variable has so great of an difference in the total deaths that nearly all the world is enacting Social Distancing as the most powerful tool to fight this new pathogen and as is often called in public policy statements, “Flattening the Curve” of infection rates and thereby the resulting death numbers. Charts like this are often used to visualize this Logarithmic Progress effect and how Simple Physical Distancing and intensive self cleaning reduces the spread of this virus.
This is vary valid math but for simplicity I included the graphic as a visualization of this effect and the net effect on our own county is this:
75% reduction in close social interaction results in 99.4% less infections in our population over 30 days and thereby 99% less deaths to locals.
Some can do MUCH less outside home interaction, but many are still on the frontlines.
A SLOW clap to those people risking their own lives for us.
