More than 50 percent of the adult population in the United States has oral herpes, typically caused by herpes simplex virus type 1 (HSV-1). Most people contract oral herpes when they are children by receiving a kiss from a friend or relative. Oral herpes is commonly referred to as “cold sores” and “fever blisters.” While symptoms of oral herpes most commonly appear on or around the lips, oral herpes is not always limited to this area.