Analyzing a Scary Death Rate

 

Analyzing a Scary Death Rate

 

It is now being reported by the following website that approximately 19% of the people whose Coronavirus cases have been resolved have died.  This is a very Scary Death Rate.

https://www.worldometers.info/coronavirus/

Here is the About Page:

https://www.worldometers.info/about/

The website calls this Death Rate the Case Fatality Ratio (CFR), and it is calculated by dividing the number of deaths by the number of closed (resolved) cases.  In other words, a case is closed when either the patient dies or recovers.

If you go to the website you’ll see two boxes right below their featured numbers.  One box is labeled “Active Cases”, and the other box is labeled “Closed Cases”.   The Scary Death Rate that I’m referring to was retrieved from the box labeled “Closed Cases”.  In that box there is also a link to a graph.

If you look at that graph you will notice the Line which represents Recoveries (green) and the Line which represents Deaths (orange) starts off close together in February and quickly begins to diverge to a more realistic Death Rate.  From early March, however, they’ve been slowly converging.

Why?  What’s happening?

After an initial emotional reaction, my rational side began to kick in.

In my younger years, I was a Data Analyst for a large electronics corporation, it was my job to “crunch” data and make sense of it.

Barring anything “sinister”, I believe I know what’s going on.

I humbly hypothesize, with this and most other infectious diseases, that the Case Fatality Ratio would be very high at the beginning of a new outbreak.  The first cases to close would be those involving the Most Affected and the Least Affected.  In other words, since the weakest die right away and the strongest recover right away, their cases are closed first.  The patients who are neither the strongest nor the weakest, the vast majority, will take longer to resolve their cases.  They’re in for a longer fight but the numbers show they are far more likely to recover than not.  Right now the World Case Fatality Ratio is very high because there has been a new outbreak in Europe and the United States, but that number will drop and the lines diverge as time passes.

It is very difficult to calculate the Death Rate of a disease in progress; the most accurate Death Rates are calculated after the disease has run its course.  Generally, the Death Rate is lower in the final numbers than when the disease was active, although, there have been a few instances where the rate actually increased.

This same website provides a good read on calculating a Mortality Rate here:

https://www.worldometers.info/coronavirus/coronavirus-death-rate/

I predict (I’m not certain) the final Death Rate for the Coronavirus will be a little higher than the regular flu, around 2% rather than 0.2%.  I don’t see it getting any higher than 5%.  The 5% number is the best the CFR has achieved so far, according to the website, but it is running better than that in China (if you can believe it).  The CFR in China is 4% and in South Korea its 3%.