Cold sores are caused by a virus called herpes simplex. Once you have the virus, it stays in your skin for the rest of your life. Sometimes it causes a cold sore. Most people are exposed to the virus when theyre young after close skin to skin contact, such as kissing, with someone who has a cold sore.

Will I get cold sores if I kiss someone with it?

Yes, you can contract oral herpes, aka cold sores, from kissing, but developing genital herpes this way is less likely. Oral herpes (HSV-1) is usually transmitted by kissing, and genital herpes (HSV-2) is most often spread through vaginal, anal, or oral sex.

How soon do you get a cold sore after exposure?

The first time you have a cold sore, symptoms may not start for up to 20 days after you were first exposed to the virus. The sores can last several days, and the blisters can take two to three weeks to heal completely.

How easy is it to get a cold sore?

Cold Sore Causes You catch HSV when you come into contact with people or things that carry the virus. For instance, you can get it from kissing someone who has the virus or from sharing eating utensils, towels, or razors. Two types of the virus can cause cold sores: HSV-1 and HSV-2.