Well, think about it. You get a cut somewhere (usually with me its the skin right on the side of my fingernails), and with all the dirt and stuff Aram is around (putting it in his glove or fielding grounders), swinging the bat, etc, it's quite easy to see how it can get infected. He probably got a small cut, thought it was nothing, and woke up one morning with it all red and swollen. It happens to me quite a bit, although never that bad.