With the Infectious Disease Balls relieve your stress and reduces your appetite. Squeeze the ball hard and gross blisters will pop out of the bag. Inner colour of ball is different than the outer colour for maximum gross-out. Leave the ball inside the mesh bag and do not remove it. While the thought of this may sound terrible, it might actually help take your mind of all the stressful things that were previously getting to you and it usually gives everyone a few good laughs.