Cold sores are created by contact with saliva or skin that starts with a primary infection. It can start if you kiss a person with a cold sore. Most are caused by HSV-1. This virus starts with small blisters that form into ulcers in your gums or mouth. Also, cold sores can spread to the eyes, fingers, genitals, and other areas. Palmetto Dental Associates, your North Myrtle Beach dentist let you know what a cold sore is and how to prevent them.