There’s herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2). “HSV-1 and HSV-2 are different but closely related viruses,” says Dr. Christine Johnston, MPH, who is the Associate Medical Director of the Virology Research Clinic at the University of Washington. Johnston explains that both are transmitted through close mucosal or skin contact with infected secretions. HSV-1 primarily causes oral outbreaks, also known as cold sores, and HSV-2 usually causes genital outbreaks. But HSV-1 can also cause genital outbreaks through oral-to-genital contact, according to the CDC. According to Johnston, genital HSV-1 is less likely to recur than HSV-2, and there’s less asymptomatic shedding (transmitting the virus without realizing it) with HSV-1 than with HSV-2.
When herpes flares up again, it is called a "recurrence" or "outbreak." Herpes does not always recur, and if it does recur, the timing and severity are different from person to person. Some people rarely have recurrences. Others have them often. Herpes is most likely to recur in the first year after infection. Recurrences may be more frequent for people with weakened immune systems.
HSV-1 and HSV-2 are transmitted by direct physical contact with a sore on an infected person. Facial or lip herpes is most often contracted by kissing someone with a cold sore. Genital herpes is most often contracted during sexual intercourse with a person who has an active genital sore. Genital herpes can also be contracted during or genital sex if a partner has labial herpes.
"Oral herpes is an infection found in the mouth, or on and around the lips, caused by the Herpes Simplex Virus (HSV)," Michael explains. "There are two types or strains of this virus called HSV1 and HSV2. Usually, the HSV1 strain infects the mouth and lips, and the HSV2 strain infects the genitals. It is however possible for HSV2 to infect your mouth and lips."