It will NOT spread once you have washed the urishiol oil off your hands, clothng etc. These are the the oils present when you originally came in contact with the the plant. Sweating may cause more irritation, itching, etc. But will cause no more spreading. Blisters also contain none of these oils, and no one else can receive it from you. It all comes down to washing A.S.A.P. after original contact with the plant. Doc |