Do you think it's time to walk back that whole "Influenza is thousands of times more deadly than coronovirus" thing?
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Let's compare deaths after the epidemic.
To do so now is dishonest.
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There are two crucially important factors to bear in mind when comparing COVID-19 with what's colloquially known as "seasonal flu".
The first is the one which the media usually focus on: the mortality rate. Current evidence (though many of the stats - especially those from China - still have reliability issues) suggests that the total-population mortality rate for COVID-19 is something between 2.5% and 3.5%. By contrast, the typical total-population mortality rate for seasonal flu in developed nations is 0.1%-0.2%.
This implies that death rates from COVID-19 might be something between 15 and 30 times higher than from seasonal flu. That's one heck of a difference. A good portion of that difference is not exactly due to any greater inherent "nastiness" of COVID-19, but is rather down to the fact that we don't currently have an effective and widely-available vaccine for it (as we do with seasonal flu). As with seasonal flu, the vast majority of all COVID-19 mortalities will be among very elderly people or those with serious underlying illnesses.
But the second - and often overlooked - factor, and one which is actually much more important when trying to predict infection levels (and thus mortality levels) is related to the ease with which the virus is spread from human to human. This is known as the Basic Reproduction Number, or R0. R0 effectively represents the average number of people who become infected from a single carrier. R0 for seasonal flu is typically 1.3. For COVID-19 (again with caveats about the quality and reliability of current data), R0 appears to be in the region of 2-3.
So this implies that the typical COVID-19 carrier will infect between 2 and 3 other people, compared with the typical seasonal flu carrier infecting 1.3 others on average. And while the difference might not seem all that large (especially when compared with the headline-grabbing difference in mortality rates), it's actually hugely significant - and it has a vast effect upon the numbers who become infected.
As an example, if you apply R0 through a set of 10 passes of seasonal flu, then the calculation goes like this: the average carrier will infect 1.3 people. Those 1.3 people will then in turn infect 1.3x1.3 people. And so on. When that process happens 10 times, the total number of infected people will be 1 + 1.3^2 + 1.3^3....... + 1.3^10. That comes out at 55 people in total.
Now let's do the same calculation for COVID-19, using a mid-range R0 value of 2.5. It comes out at......... 15,893 people in total.
So: 10 onward transmissions of seasonal flu end up on average infecting
55 people in total; 10 onward transmissions of COVID-19 may well end up infecting (conservatively) nearly
16,000 people in total.
This ought to illustrate how COVID-19 appears to be spreading far more easily than seasonal flu, with huge consequential effects. And taken together with a mortality rate which appears to be an order of magnitude higher than that of seasonal flu, it should be pretty easy to see the gigantic difference in scale of the problem posed by COVID-19 when compared with seasonal flu.
