Infection with the herpes simplex virus around the border of the lips.

Herpes labialis is an infection with herpes simplex virus around the border of the lips. These types of infections are also called cold sores, fever blisters, and oral herpes.

Herpes labialis causes tiny, fluid-filled sores. Oral herpes spreads through close personal contact, such as kissing. Blisters can recur.

Medicines can speed healing.