Sorry, but your back of the envelope calculations suck. There is not a 5% infection rate, and there is not a 10% mortality rate.
HTH
To give you some perspective, imagine these two scenarios.
a) You choose at random a +50 years old men living in Africa. The chance of him living with HIV is close to 15%.
b) You take a random person out of the US population. Around 1 million people in the US live with HIV. That's 1 in 327, or 0.3%.
a is 50 times higher than b. That's an increase of 4900%
So, you see, things like age group and location matters a lot. Just like with HIV, coronavirus deaths are not evenly spread among the whole population.