Please correct my math if you find an error.
Some straight data on the flu: (this included complications associated with the flu = pneumonia mostly)
I averaged all of the data from 2010 thru 2019:
28,650,000 Estimated Symptomatic Illnesses per year
13,300,000 Estimated Medical Visits per year (-46% of people go to Dr when they get the flu)
450,000 Estimated Hospitalizations per year (1.56% end up in hospital. Mostly >65yr old folks)
37,500 Estimated Deaths per year
0.13% = Deaths/Symptoms (for every 10,000 people with the flu; 13 will die)
0.28% = Death/Medical visits
8.39% = Deaths/Hospitalizations (8% of people put in hospital due to flu, don't come home) (This surprised me)
Link to Data, CDC, US: https://www.cdc.gov/flu/about/burden/index.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fflu%2Fabout%2Fdisease%2Fburden.htm
Not exactly: Typically a very high percentage are folks over 65yrs age ~90% range.
But: Some flu strains are worse on kids, and one of the flu strains a few years back was attacking healthier 25-40yr old people.
I, too, was surprised the 8% of the people that go to the hospital with the flu never come home.