The COVID-19 pandemic could be resolved in 30 days for about $2 per person, simply by taking affirmative action to raise vitamin D levels among the general public. Optimizing your vitamin D could reduce your risk of severe COVID-19 by 90% and your risk of dying from it by 96%.
https://articles.mercola.com/sites/articles/archive/2020/07/09/optimal-vitamin-d-levels-for-coronavirus-crisis.aspx
