Oral sex is a possible method of transmission for a herpes infection. The typical way that herpes is spread through oral sex is when a person with an oral herpes infection, or a herpes infection about the area of the mouth, passes their oral herpes infection to another person's genitals by performing oral sex. It's also possible that a person with genital herpes could pass their infection to someone's mouth area through having oral sex performed on them. A herpes oral sex infection is most likely to be spread during an active outbreak of herpes symptoms. Though it does happen, oral sex is not a typical method for the transmission of a herpes infection. Oral herpes and genital herpes are caused by different variations of the herpes simplex virus, and oral herpes doesn't thrive below the waist and genital herpes doesn't thrive above the waist. Oral herpes infections don't often transmit to the genitals, and genital herpes infections don't often transmit to cases of oral herpes.