Impetigo Impetigo is a contagious skin infection that often causes red sores, blisters, crusting, or honey-colored scabs. It is usually caused by bacteria, commonly Staphylococcus aureus or Group A Streptococcus. Impetigo is more common in children, but adults can get it too, especially when bacteria enter through irritated, scratched, or broken skin. What does impetigo look like? Impetigo may cause: Red sores or patches Blisters that break open Honey-colored crusting Itching