At my school me and my friends play around punch and stuff like that like you know some do. And me and my friend were messing around and he had a guitar string he was poking me with and I wasn't worried but when I looked at my arm the holes were so small I could barely see them and some were just barely bleeding. Is there anyway if this guy had something and he had accidently gotten any of his blood at the tip of his guitar string could he of given me something?