Reports of a mysterious rash developed by participants of the St. Louis County Mighty Mud Mania have grown. More more than 300 reports have filtered in to the county. The Mud Mania held this past weekend features a mud-filled obstacle course, that leaves most children covered head-to-toe in mud. County health officials say the rash stems from coming into contact with certain bacteria. They say it shouldn’t need treatment and normally goes away in a couple of days.