Cytokine storms are similar to anaphylaxsis. Taking Vitamin D will prevent them in Covid not sure about allergic reactions but since I have had anaphylactic episodes, I take Vit D every day, in case it does work.

Basically what happens is the body recognizes something it thinks is foreign and reacts. In a storm, the reaction keeps ramping up and doesn't stop. Vitamin D keeps that rise in check with Covid.