HSV type 1 most commonly infects the lips causing sores known as fever blisters or cold sores, but it also can infect the genital area and produce sores there. HSV type 2 is the usual cause of genital herpes, but it also can infect the mouth during oral sex. A person who has genital herpes infection can easily pass or transmit the virus to an uninfected person during sex. Occasionally, sores also appear on other parts of the body where the virus has entered through broken skin. HSV remains in certain nerve cells of the body for life, and can produce symptoms off and on in some infected people.
Most people get genital herpes by having sex with someone who is having a herpes outbreak.
This outbreak means that HSV is active. When active, the virus usually causes visible sores in the genital area. Sometimes, however, a person can have an outbreak and have no visible sores at all. A person with genital herpes also can infect a sexual partner during oral sex. The virus is spread only rarely, if at all, by touching objects such as a toilet seat or hot tub.