HSV-1 is transmitted orally (think: by kissing or sharing utensils), and although it most often causes cold sores around the mouth, it can be a cause of genital herpes, too (it can be transmitted from mouth to genitals during oral sex). But most cases of genital herpes are caused by the HSV-2 virus. Still, there's no cure for either form of the STD—the painful bumps come back whenever your immune system's been compromised in some way.