Herpes zoster can usually heal and thus leave no scars, but in rare cases the rash is more deeply damaged and can involve the dermis, which can leave scars. Herpes zoster is a contagious skin disease caused by varicella-zoster virus infection, which is mainly a unilateral patch of erythematous skin with clusters of blisters and significant pain. If the erythematous blisters are heavily involved and reach the dermis, they can leave scars in the healing process, so it is important to treat shingles as early as possible to avoid scarring.