ELDERBERRY SYRUP is very strong anti-viral herb, the only one known. First sign of a sniffle consider trying alkaline producing elderberry syrup (Sambuco©). Avoid the oxalate rich whole fruit ↑ oxalates, detrimental PKD/PLD. Researched by an Israeli herbalist & found to be the one food that actually exerts an anti-viral influence. Its use was developed for Israeli troops in battle. It is great for allaying a cough or cold during the flu season.