I can get it in the winter by walking past a vine and barely touching it. I had an environmental engineer tell me that when he works in the field he takes baby wipes. The wipes take the oil off immediately. Cortizone cream and antihistamines help me if I get the rash. If it is real bad I get a cortizone shot. Also try cold water or a bag of ice. The doctor told me it calms the histamines.