Rhodes, J. M., Subramanian, S., Laird, E., & Anne Kenny, R. (2020). Low population mortality from COVID‐19 in countries south of latitude 35 degrees North–supports vitamin D as a factor determining severity. Alimentary pharmacology & therapeutics.
This article links latitude to vitamin D status and COVID-19 deaths. The COVID-19 death rate is related to a higher altitude. Vitamin D deficiencies are also related to a higher latitude and to risk factors for COVID-19 disease severity. Therefore vitamin D status and COVID-19 disease severity are linked. It is clearly stated that increased vitamin D status is not directly linked to preventing COVID-19, but rather to reducing the disease severity and hence preventing deaths.