Wednesday, 13 May 2020

‘Making sense of COVID-19 fatality rates’ | Star Tribune

I have no idea about the Star Tribune. I just came across this article when I was researching the Infection Fatality Rate (IFR). This is the death rate as % of all cases of infection. Because we don’t know “all” cases, we have to guess, and the current best guesses are that the IFR of Covid-19 is between 0.05% and 0.5%. 

Meantime there is  a spreadsheet summarising 54 studies around the world estimating the IFR. It’s here. It’s average is 0.28%. Given that these are actual figures from actual proper studies, I’d go with that for now, with reasonable confidence as it’s smack bang in the middle of the above estimates.

The Case Fatality Rate (CFR) is easier to measure.  It’s the number of deaths over the known, tested infected people. You can get it anytime from Worldometer.  It’s currently just above 6%. That is between ten and a hundred times more than the estimated IFR rate. Reason being of course, that the number of asymptomatic cases and also the number that have had the virus and got over it without reporting, is high. 

In sum: 
IFR = 0.28% (with a range of 0.05% to 0.5%) 
CFR = 6.5%

The IFR is around two to three times worse than an average flu season. It begs the question: we do precisely zip when the flu hits. Does it make sense to crash the economy for a risk that is two or three times larger?  And for those that are pro-Lockdown, what is the alternative? When does it end? What are there criteria for ending? Given that we’ve already reached the criteria we all set at the beginning: “flatten the curve’ and “protect the health system”.

In the comments to the Star Tribune article there’s this exchange (click to enlarge):
Click to enlarge
@Sfitz and @bigwolf are employing straw man arguments. No-one is saying we should have the “right to do whatvever you want”, or the “right to do as they please”. Just that people ought to have the chance to get back to work and make living for themselves and their families without putting the most vulnerable at too much risk. 
Those at risk would include me, 70+, male, high BMI. But unlike @sfitz, I don’t want the world to stop because of my risk.
I don’t want my offspring to have their lives shattered because I fear some risk. Mr @sftitz can stay at home if he’s worried. Or go for a walk and stay distanced. I don’t see what extra risk it is to him if people return to work, or reopen their nail salon, or go to the beach. Especially now people have got used to distancing and disinfecting, the two best ways to stop its spread.