EE WAS HOLDING A SQUARE ON REBAR STRUCTURE TO BE WELDED. WITNESS STRUCK AN ARC WHEN THE MIG WIRE DEFLECTED OFF STRUCTURE INTO THIGH. HOT WIRE CAUSED BURN. EE APPLIED FIRST AID & RETURNED TO WO RK. SEVERAL DAYS LATER, THIGH BECAME RED & IRRITATED, SOUGHT MEDICAL ATTENTION. DR. PRESCRIBED ANTIBIOTICS.