Number sign. Not to be confused with the Chinese character äº, the sharp sign (â¯), the viewdata square (â), the numero sign (â), the equal and parallel to symbol (â) or the game Tic-tac-toe's grid. The symbol # is most commonly known as the number sign, hash, or pound sign.
The poison ivy rash is not contagious. When a person touches the poison ivy leaf, a substance on the surface of the leaf (a resin) rubs off. Over the next 48 to 72 hours the skin reacts to the resin by becoming red and developing bumps and blisters at and around the site where the resin was.
Quick Answer. A poison ivy rash is not contagious and coming into contact with a blister or its fluid content will not transmit the rash to another person. What causes the rash is the oil called urushiol. Plants such as poison ivy, sumac and poison oak contain this chemical which causes allergic reactions in people, states Mayo Clinic. Continue Reading.