I made this remark in one of Mark Sumner’s excellent COVID-19 diaries, but I think it’s important to bring it to wider attention.
As many of you have heard by now, the WHO Director recently gave a speech in which he announced that 3.4% of COVID-19 cases thus far have ended in death. This is completely accurate, as far as it goes. If you take the total deaths reported thus far worldwide (3168) and divide by the number of cases reported (92880) you get 0.0341, or 3.41%.
But what people really *want* to know is, if I get this thing, how likely am I to die? The calculation I just described can’t tell you that. The reason is that China dominates both the number of cases (80152 of 92880) and deaths (2945 of 3168). Neither the numerator nor denominator in that number is especially applicable to the situation you are likely to find yourself in should you get infected.
China has been dealing with this virus since before anyone knew what it was or how to treat it. Even in China, the death rate is dominated by Wuhan, where the virus emerged and spread before anyone knew what it was, and overwhelmed the health care system. Overall the death rate in China is about 3.6%, but if you exclude Wuhan, it is somewhere around 0.7%.
This is a very serious disease; assuming the 0.7% rate is more typical, that’s still an order of magnitude more deadly than most strains of flu. It also poses a more serious threat to people with chronic health problems like diabetes and respiratory disease. We need to focus on preparing to treat it here and contain its spread.