Most people will have come into contact with the virus between the ages of three and five years-old but will not show any symptoms until after puberty. HSV invades the cells of the epidermis, the outer layer of the skin, causing fluid-filled blisters to appear. The virus travels from the epidermis along the nerve paths to the roots of the nerves where it becomes inactive. A weakening of the body's defences, due to a severe cold for example, can lead to a reactivation of the virus and a return of the blisters. The primary infection can progress in different ways.
Some people only have very mild symptoms or none at all.
The first outbreak starts one to three weeks after the virus has been contracted. It subsides spontaneously within a few weeks. Later, if HSV is reactivated, the blisters will return The first symptom of an outbreak is an unpleasant tingling feeling in the skin . After a short while, a number of fluid-filled blisters appear The sores become covered by scabs which typically fall off after eight to ten days . The virus can spread until the sores are completely covered by scabs.