If you pick at sores or scratch itchy bites, you may cause bacteria to enter your skin and cause impetigo.
Bacteria get below the surface of the skin, usually by some sort of break in the skin.
Once the bacteria get into the inner layers of the skin, they grow and multiply, creating a blister. Usually, this blister becomes filled with pus and bursts, leaving a crust. Both are commonly found in the environment and on the surface of most people s skin. 4 of 13 Impetigo shows up as a rash that may occur anywhere on the body and commonly affects the face and other exposed areas of the body. The margins of the rash are usually fairly sharp.