The second article i linked to sites three reasons for lower mortality rate in Africa than other countries, one of which we have already mentioned, which is the younger demographic.
Quoting the article:
"Factors influencing the low mortality rate in Africa
Demographics play an important role in reducing mortality from COVID-19. Research has shown that the demographic of 65–74 years is 35 times more likely to become hospitalized from SARS-CoV-2 infection and 1100 times more likely to die from COVID-19, compared to a reference demographic group of 5–17 years. Africa has quite a young population with a median age of 19.7 years. In comparison, some of the hardest-hit countries have much higher median ages (e.g., the median age in the UK is 40.5 years and in the USA is 38.5 years).
It is well documented that people with pre-existing conditions (e.g., diabetes, hypertension, etc.) have a higher risk of moderate to severe complications from COVID-19 infection. African countries have a low prevalence of these conditions, which might be another factor for the lower mortality rate.
Another factor that may be affecting the COVID-19 burden in Africa is “trained immunity.” Four key elements contributing to trained immunity in Africa are (i) prior vaccinations like BCG, (ii) exposure to various commensal microorganisms, (iii) prevalence of other infectious diseases, and (iv) use of herbal plants and natural remedies. Genetic factors might also be benefitting the African population. SARS-CoV-2 spreads through targeting the human angiotensin-converting enzyme-2 (ACE2) receptor. African individuals have been shown to have less expression of ACE2, making it difficult for the virus to infect cells."
The article:
https://www.news-medical.net/news/20210818/Why-have-COVID-19-caseloads-been-comparatively-low-in-Africa.aspx