Herpes labialis or "orolabial herpes" is an infection of the lip by herpes simplex virus (HSV-1). An outbreak typically causes small blisters or sores on or around the mouth commonly known as cold sores or fever blisters. The sores typically heal within 2–3 weeks, but the herpes virus remains dormant in the facial nerves, following orofacial infection, periodically reactivating (in symptomatic people) to create sores in the same area of the mouth or face at the site of the original infection. 80% of adults in the United States are carriers of the virus that causes cold sores, and more than 50 million adults in the U...