Herpes simplex

Herpes simplex, infection of either the skin or the genitalia caused by either of two strains of herpes simplex virus. Herpes simplex virus type 1 (HSV-1) is transmitted orally and is responsible for cold sores and fever blisters, typically occurring around the mouth, whereas herpes simplex virus type 2 (HSV-2) is transmitted sexually and is the main cause of the condition known as genital herpes.