The virus responsible for cold sores is highly widespread, with an estimated 50% to 80% of adults in the United States carrying it. Although not everyone infected will experience outbreaks, cold sores remain a common condition. For those who do get them, the painful and unsightly blisters can cause significant discomfort and emotional stress.

Cold sores are caused by a common virus that affects up to 80% of U.S. adults. While not all carriers show symptoms, those who do often experience painful, stressful blisters.