If you have symptoms of a herpes outbreak, even if mild, there is a risk of transmitting the infection to your partner. In fact, even if you don't have a herpes outbreak, you could transmit the infection to your partner. Whether you have an outbreak is not a reliable way to prevent transmitting infection. Even people on medication can transmit infection -- even with no outbreak. The best way to help prevent infection is to always use a condom. Here's a study from January that further explains. Hope that helps.
It needs to be added to the doctors answer that if you have blisters anywhere on your private area that is not used for "sex", a condom will not help. Example: if you have blisters on the bend of your leg or tip of your butt cheek, a condom isnt going to help. WHATEVER you do...no matter what...do not EVER have sex with someone if you know you have herpes without telling your partner. You might think you are safe, but in fact you could spread it. You will be shocked how many people have herpes. You will be shocked how your partner reacts if they care about you. Heck, you might be shocked on what they confess to you.
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