Most of the time, the virus rests in the nerve endings. When the virus becomes active again, the sores and blisters will come back. These blisters and sores are usually less painful and heal faster. How often the virus becomes active again varies from person to person. Factors that may trigger the virus to become active again include sunlight, injury to the infected area, fever, menstruation, poor diet, stress, and lowered immune system.
Some people can feel tingling in the infected area before an outbreak of blisters.
Herpes can be diagnosed by physical examination and medical history. A swab of the fluid taken from the sores or blisters can be sent to a laboratory for testing. Herpes sores can become infected wit bacteria. Women with an initial severe outbreak may have a hard time passing urine. Herpes of the eyes can cause blindness.