What is herpes?

What is herpes?

Herpes labialis (cold sore, fever blister) is a commonly occurring ailment. Approximately one-third of all infected patients suffer relapses. Herpes labialis is a rash of the skin and mucous membranes (in particular, the lips) and is characterized by erythema and blisters that are preceded and accompanied by burning pain. It is a harmless but often annoying ailment in immunocompetent patients and it usually heals spontaneously within 10 days.

• Treatments for herpes

Herpes labialis is contagious for individuals who have not been previously infected by the virus and for those with weakened immune systems (eg, those with HIV infection or undergoing chemotherapy). In addition, herpes labialis infection can result in genital herpes through oral to genital contact.

Herpes labialis is caused by herpes simplex virus type 1 (HSV-1). Infection with type 2 virus can also lead to (primary) herpes labialis, but this type rarely causes a relapse of the ailment. The primary infection with HSV-1 usually occurs before the age of 20 years. Antibodies against the virus can be found in about 80% of all adolescents. Probably because of the improved socioeconomic circumstances in industrial countries, individuals are older when first infected than was the case some decades ago. As a result of this epidemiologic shift, it is becoming more common for the primary infection to manifest as genital herpes because of orogenital contact.

After primary infection, the virus recedes via the sensory nerve into the respective ganglion (usually the trigeminal ganglion), where it lies latent throughout the individual’s lifetime. Stimuli such as fever, menstruation, sunlight, and upper respiratory infections can reactivate the virus, after which it returns to the epithelial cells via the sensory nerve. In contrast to the primary infection, during which all oral mucosa can be affected, relapsing infections are limited to the mucosa of the hard palate or, in older children and adults, the lips.

The natural course of dis-ease progression is decreased frequency and severity of recurrences over time. However, roughly a third of patients do not experience this time-dependent regression.