One more study - "Patients with vitamin D deficiency (<20 ng/mL) were 14 times more likely to have severe or critical disease than patients with 25(OH)D ≥40 ng/mL"
This study was conducted of hospitalised patients admitted prior to the vaccines, so these are only Vit D effects.
What is interesting is that *NO ONE* over the age of 65 (the most vulnerable age group: others don't much matter) with Vit D> 20 faced a critical threat - which I suppose are people close to death.
That's why deaths of dark skinned doctors in the UK dropped to ZERO within 2 weeks of supplementation.
If I were a risk-based analyst, I'd recalculate r based on actual risk of death faced by age group (1000 times more in higher age groups than in lower ones) - and then r might end up closer to 1. A 100% remedy to eliminate covid deaths? - almost a sterilising vaccine.
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0263069
