Herpes is most contagious while the blisters or blister fluid is present and continue to be until they have completely healed. We recommend avoiding skin-to-skin contact (kissing, sexual contact including oral sex and masturbation) or sharing utensils, cups or other items during this time to reduce transmission.
Using barriers, such as internal (female) or external (male) condoms and dental dams, can reduce the possibility of getting or passing herpes, but often do not completely prevent transmission because they do not cover the entire genital area or the blisters.
Condoms can also be used on sex toys.
Wash your hands if you have touched the blisters to prevent transferring the virus to another person.
Latent infection (asymptomatic transmission or viral shedding)
HSV can still be passed when there are no symptoms (called asymptomatic shedding). While this is less likely, there is no way to predict when or how often this occurs in an individual person.
Taking antiviral herpes medications can reduce, but will not eliminate, transmission risk from asymptomatic shedding.