The medical term for shingles is herpes zoster. Herpes in Greek means snake and zoster means girdle. This was meant to capture the painful feeling that shingles can bring, like being tightly wrapped round the body like a snake.
After an episode of chickenpox, the virus remains inactive in the nerves of the spine for many years, sometimes decades. Shingles develops when the virus becomes active again. Illness, stress or just getting older can re-activate the virus and trigger an attack.
Why shingles happens is not fully understood, but the most likely reason is a reduction in the immune system's ability to keep the inactive virus under control.
