We have been recommending that you take an alcohol extract of dandelion leaf when you discover you have been exposed to COVID, or when you have had a high chance of exposure, like after an airplane flight. This is based on research showing that dandelion leaf prevents the COVID virus from entering and infecting your cells. Must be started within 24 hours of exposure to have a chance of working.
Recommended Dosing is 2 droppersful four times per day, for five days. (A droppersful is what you can draw up with one good squeeze)
Reference: https://doi.org/10.3390/ph14101055 (A PDF of the article "In Vitro Effect of Taraxacum officinale Leaf Aqueous Extract on the Interaction between ACE2 Cell Surface Receptor and SARS-CoV-2 Spike Protein D614 and Four Mutants" can be downloaded below.)