Thought to be caused by an overactive immune response, eczema cannot spread from one person to another, according to WebMD. Eczema is almost always itchy, and most commonly presents on the face, hands, wrists, feet and back of the knees.
While the exact cause of eczema is unknown, it most often affects people in families with a high instance of allergies or asthma, according to WebMD. Often triggered by certain conditions or substances, eczema can be largely managed by avoiding irritants. There are no tests that diagnose eczema; however, a doctor can typically diagnose the condition by examining the skin.