Can I kiss my boyfriend if he has a cold sore?

Cold sores are medically called herpes simplex 1 and usually occur on the lips. Some are unlucky and get an outbreak inside the mouth or up the nose, but the vast majority get an outbreak on and around the lips. The outbreak starts with a tingling or some kind of soreness in the skin. Then small clear blisters appear in larger or smaller clusters. This is when you need to be careful, because the fluid inside the blisters is full of infectious herpes virus. You can carefully poke holes in the blisters with a sewing needle that has been cleaned with alcohol. Then you can carefully squeeze the fluid out of the blisters with a cotton pad/kitchen roll. Be very careful to wash both your hands and the needle thoroughly afterwards.

Don't kiss anyone if you have a herpes outbreak, as it is very contagious. The vast majority of people infected have been infected before they are 5 years old, and they have usually been infected by a family member or at their daycare/nursery. Herpes cold sores are most contagious during outbreaks, but you can actually infect others before you even know you have an outbreak. Similarly, you can be infected by others before they even know they have an outbreak. Because the virus is so contagious, it is almost impossible to stop the chain of transmission.

The only thing you can/must do, unless you are completely paranoid or moving to a desert island or never kiss anyone, is to pay close attention to when you get a cold sore/herpes outbreak. React at the slightest sign of herpes and avoid kissing. Start treatment as soon as you feel an outbreak and continue until the wound has scabbed over. Wash your hands often and don't touch the wound. Avoid direct sunlight on the wound and apply the gel you use for herpes frequently. Wait until the scab is gone and then you can kiss again, all you want.