[CardinalSagehen]

I don't know if this applies to most of Africa, and it's just a theory that might have been shared here previously, but I found the following study to be interesting.  It suggests that countries with high vaccination rates for tuberculosis, such as Germany, have done much better in terms of COVID-19 mortality.  The theory is that there may be some cross-immunity.  Almost all countries in Africa have a current policy to vaccinate for TB, although I don't know how successful those policies are. Places like the US, where TB has not been endemic, have never had a TB vaccination policy.

https://www.pnas.org/content/117/30/17720.full

A strong correlation between the BCG index, an estimation of the degree of universal BCG vaccination deployment in a country, and COVID-19 mortality in different socially similar European countries was observed (r2 = 0.88; P = 8 × 10−7), indicating that every 10% increase in the BCG index was associated with a 10.4% reduction in COVID-19 mortality. Results fail to confirm the null hypothesis of no association between BCG vaccination and COVID-19 mortality, and suggest that BCG could have a protective effect. Nevertheless, the analyses are restricted to coarse-scale signals and should be considered with caution. 

[CardinalSagehen]

I don't know if this applies to most of Africa, and it's just a theory that might have been shared here previously, but I found the following study to be interesting.  It suggests that countries with high vaccination rates for tuberculosis, such as Germany, have done much better in terms of COVID-19 mortality.  The theory is that there may be some cross-immunity.  Almost all countries in Africa have a current policy to vaccinate for TB, although I don't know how successful those policies are. Places like the US, where TB has not been endemic, have never had a TB vaccination policy.

https://www.pnas.org/content/117/30/17720.full

A strong correlation between the BCG index, an estimation of the degree of universal BCG vaccination deployment in a country, and COVID-19 mortality in different socially similar European countries was observed (r2 = 0.88; P = 8 × 10−7), indicating that every 10% increase in the BCG index was associated with a 10.4% reduction in COVID-19 mortality. Results fail to confirm the null hypothesis of no association between BCG vaccination and COVID-19 mortality, and suggest that BCG could have a protective effect. Nevertheless, the analyses are restricted to coarse-scale signals and should be considered with caution.