Herpes zoster. A 10-day-old herpes zoster (shingles) rash on a woman's face. This condition is caused by infection of sensory nerves with the varicella-zoster virus, which also causes chickenpox. The virus can remain dormant in the body for years after chickenpox, becoming active again if the immune system is weakened. It attacks nerves feeding the skin, causing a rash of small, painful blisters in a defined area. Nerve damage can result in the pain persisting for months or years after the blisters have disappeared. There is no effective cure. In this patient the virus affected the maxillary (VII) branch of the fifth cranial nerve, a rare manifestation of shingles.