A child with Epidermolysis Bullosa (EB) is afflicted with a type of inherited skin disorder that causes blisters after even the mildest trauma. Most commonly, EB causes blisters on the skin, but EB can also affect the mouth, esophagus, lungs, muscles, eyes, nails and teeth. Depending on the type of EB, the effects of the skin disorder can be mild, disabling, or life threatening. EB is never contagious because it is a genetic skin disorder.
There are three types of EB, all caused by a different genetic mutation: EB simplex (EBS), Junctional EB (JEB) and Dystrophic EB (DEB). EB simplex is the mildest and most common form of EB, while Junctional EB and Dystrophic EB are relatively less common and affect the patient more severely.
I highly recommend the following link on the Stanford Dermatology Website to better understand EB.