Herpes zoster (shingles) is an infection with the varicella zoster virus (VZV) that causes a painful skin rash usually affecting one side of the face or body. Some people feel pain or itching in the area where the rash is going to appear. Blisters from the rash form scabs after about 1 week, and the rash usually clears up in 2–4 weeks. Shingles can also cause fever, headache, chills, and stomachache. Shingles can cause vision loss when it affects the eyes.
Shingles is caused by the same VZV that causes chickenpox. In people who have had chickenpox, the virus stays in the body in an inactive state. Though no one knows why, the virus can become active again. This usually happens after age 60 years, but people of all ages can develop shingles. The risk of getting shingles increases with age. Some people with shingles have a long-term side effect called postherpetic neuralgia (PHN). PHN causes burning pain of the skin. The risk of developing PHN also increases with age.
Almost 1 out of every 3 people will get shingles. After age 85 years, 1 out of every 2 people will get it. Most people get only one case of shingles in their lifetime, but some people get it more than once. Shingles cannot be spread from person to person, but people who have never been exposed to VZV can get chickenpox if they come in contact with open blisters from someone with shingles.