Shingles. Shingles occur when the varicella-zoster virus which also causes chickenpox erupts after the initial infection, sometimes many years later as in the case of this 90-year-old woman. Once infected, the virus can remain dormant in the body for years. It reactivates if the immune system is weakened, attacking the nerves feeding the skin. The result is a painful rash of small, blisters in a defined area. The pain can persist for months and even years, leading to possible nerve damage and scarring. There is no cure, but there is a vaccine that may prevent shingles.