Shingles is a disease of the skin produced by the same virus that causes chickenpox.
Why the virus reactivates is unknown. What triggers an attack of shingles is unknown. Exposure to someone with active chickenpox does not reactivate the virus to cause shingles. However, direct exposure to someone with shingles can cause chickenpox in someone who has not had it before. Shingles disease is more often seen in the elderly than in younger adults or children.