Cold Sores

Cold sores are caused by the herpes simplex virus. A first cold sore usually occurs in childhood. The virus infects through the moist 'inner' skin that lines the mouth. It is commonly passed on by skin contact such as kisses from a family member who has a cold sore.
You may feel a tingle or itch before the blisters appear, usually around your lips or nose. This can last several hours, or up to a day or so. After the tingle, one or more blisters appear which are usually sore. They may weep and take several days to scab. The scab slowly disappears over a week or so leaving no scar.