As much as I believe in the Chinese gov fudging the numbers, there is no way for a line medical workers to know or even estimates the true numbers at the scale of ten thousands patients.
I've been trying to understand the number from the Spanish flu and it seems utterly confusing for some reasons.
The consensus seems to be 30% population of the world was infected, with a case-fatality rate of 2.5% (which is another commonly quoted number), it doesn't add up to 5% of the world's population. The case-fatality rate will have to be around 20% for it to kill that many people. This happens even in the same academic paper (for example: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3291398/ )
> An estimated one third of the world's population (or ≈500 million persons) were infected and had clinically apparent illnesses (1,2) during the 1918–1919 influenza pandemic. The disease was exceptionally severe. Case-fatality rates were >2.5%, compared to <0.1% in other influenza pandemics (3,4). Total deaths were estimated at ≈50 million (5–7) and were arguably as high as 100 million (7).
?!
Can anyone more knowledgable explain what is going on with all those numbers?