Fever Blister (Cold Sore) (Labial Herpes) (Febrile Herpes)
A fever blister (aka cold sore, labial herpes, febrile herpes) is a small sore on the face, lips, or mouth that causes pain before bursting and crusting over. The favorite locations are on the lips, chin or cheeks and in the nostrils, less commonly the gums or roof of the mouth (the palate). Fever blisters are caused by the herpes simplex virus type 1. It lies dormant in the body and is reactivated by factors such as stress, sunburn, or fever (from a wide range of infectious diseases including colds). Recurrences are less common after age 35. Sunscreen (SPF 15 or more) on the lips prevents recurrences of herpes from sunburn. The virus is highly contagious when fever blisters are present and is spread by kissing. Children become infected by contact with someone who has a fever blister and then they spread the virus by rubbing their cold sore and touching other children. There is no way to eradicate the virus, but medications can relieve some of the pain and discomfort including ointments that numb the blisters, antibiotics that control secondary bacterial infections, and ointments that soften the crests of the sores. Acyclovir, an antiviral drug, prevents the herpes simplex virus from multiplying and, in pill form, is said to reduce the symptoms and frequency of recurrence. Fever blisters can occur in epidemic proportions. About 100 million episodes of recurrent fever blisters occur yearly in the United States alone.