If not, then maybe…

if it’s not that African Africans are immune to COVID-19, then it could be that all unhealthy Africans did not last long enough to be caught by COVID-19.
Could it be that our health care is so poor that only really healthy people can survive?
Perhaps countries with better health care systems are receiving a higher mortality rate from COVID-19 due to their high life expectancy rate, meaning they have a lot of senior citizens.

#theory