Search Results for "cause of cold sores"

Cold sores are caused by a virus, the herpes simplex virus or HSV. There are two kinds of herpes simplex virus, called type 1 and type 2. While both types can cause cold sores, type 1 is the variety usually responsible. Type 2 HSV is found in genital herpes and is much more rare than type 1 HSV. HSV-1 is the most common cause of cold sores. Most people are exposed to HSV-1 between the ages of three to five. There are many ways that a person can become infected by HSV-1, including among them coming into close contact with a person who has a cold sore,