It is a type of herpes but not an STD. Cold sores are type 1 virus. Genital herpes is type 2 virus. You can get type 1 with the exchange of saliva or oral sex. You could have been kissed as a baby by someone that had type 1 herpes and didn't even realize they were infected. or shared a snack with another child that had the virus and didn't know it. It can be transmitted many, many different ways but saliva had to have been exchanged. Have your family Dr. write you a script for zoviax cream and use when you first feel the cold sore starting. Best wishes.