I bolded the part of your post that I would like to comment on. We have enough data now to show that African Americans and darker-skinned populations in some countries have been hit much harder than whites. In Sweden, for example, minority populations have 3-5 times more cases/100,000 population than native Swedes. What do all these darker-skinned populations have in common?
Genetically, they lack the ability to store vitamin D. Blacks in the US are three times more likely to have vitamin D deficiency than whites. Native Swedes have one of the highest vitamin D levels in the world. What countries have the lowest levels? That would be Italy, Spain, and the US... all countries that have been hit hardest.
I'm seeing an alternative medicine MD next week. Before we even got off the phone, we were discussing the data on vitamin D, magnesium, and zinc.
So why are the African nations coming through this pandemic with LOWER rates of COVID?
I've also wondered why the prevalence of COVID 19 is less in African nations. Obviously, something other than vitamin D is dominating the population's resistance to the disease. Perhaps it's a combination of three major factors, plus vitamin D levels.
1. OBESITY: The obesity rate of adult African Americans is 49%, according to the CDC. The obesity rate in Ethiopia is 4.5%; Congo, 9.6%; Gambia, 10.3%.
1A: OVERWEIGHT: As a continuation of the overweight correlation to COVID, 73% of adult African Americans are overweight. It's not much better with the white US population at 65%. To pick one African nation example, in Ethiopia, 6.9% of women and 1.9% of males were overweight in 2016. (NIH data). Merely being overweight, not yet obese, also seems to be a factor in COVID severity.
2. DIET: Africans have a much different diet and eat far less packaged and fast foods.
3: IMMUNE SYSTEMS: It's speculation my part, but I imagine that as a population, Africans have a stronger immune system for viruses because they are constantly exposed to a lot of very nasty illnesses and viruses. Malaria, in particular, might prove to be an interesting side study.
Obviously, there could be other factors, but the point remains that studies in the US, China, Sweden, Singapore, Turkey, Canada and other nations that I can't think of off the top of my head show a very strong correlation between vitamin D insufficiency and prevalence/severity of COVID 19.
tl;dr Vitamin D might be the secret weapon against COVID 19. At worst, there are no side effects taken at the recommended dose and it costs only ten cents a day. Take it. Now.