Dr. Thaden is correct (after all, he is an M.D.!) about alcohol, as either ethyl or isopropyl will kill bacteria, yeasts, molds, etc. (Whoops! make that Ph.D., like meself) It will not kill viruses however, they must be attacked with bleaches, phenols (not recommended, pretty nasty stuff) or other more highly toxic chemicals which should NOT be used to clean one's harps. Bill