Herpes simplex is a contagious skin disease caused by infection with the herpes simplex virus (HSV). The clinical features of herpes simplex are clusters of small, unilocular blisters on the skin and mucous membranes, mainly on the face or genitals, and are prone to recurrence; the pathogen is a virus that often occurs on the upper lip or face. The symptoms are local itching first, followed by the appearance of blister-like protrusions containing clear fluid, slight pain, and self-healing after one or two weeks of scab formation. HSV can cause intrauterine infection, and the fetus may be born with various forms of congenital malformations or developmental disorders. It is one of the common causes of the so-called "TORCH" syndrome.