Although latex condoms can reduce the risk of transmitting most STIs by 98%, condoms don't prevent herpes transmission. This is because not all herpes sores occur in areas that are covered by a condom.
If you're experiencing an active outbreak, you can prevent herpes transmission by:
avoiding sexual activity (kissing and oral, vaginal, and anal sex) until symptoms go away
washing your hands thoroughly and applying medication with cotton swabs to reduce contact with sores
Taking a daily antiviral herpes medication can also help prevent transmission, shorten outbreaks, and manage symptoms.