Genital herpes is caused by herpes simplex virus (HSV), of which there are two types: HSV-1 and HSV-2. Primary infection (true first episode) is where symptoms occur in a person who has had no previous exposure to HSV. Classically genital herpes was caused by HSV-2, but now HSV-1 is more common due to the increase prevalence of oral sex. The clinical features and course of primary genital herpes caused by both HSV-1 and HSV-2 are indistinguishable, but asymptomatic primary infection is more common with HSV-2. Prior orolabial infection with HSV-1 protects against genital HSV-1 and has an ameliorating effect on HSV-2 genital herpes.
|Local symptoms||Painful ulceration|