About 25 percent of all adults, mostly otherwise healthy, will get shingles during their lifetimes, usually after age 40. The incidence increases with age so that shingles is 10 times more likely to occur in adults over 60 than in children under 10. People with compromised immune systems - from use of immunosuppressive medications such as prednisone, from serious illnesses such as cancer, or from infection with HIV - are at special risk of developing shingles. These individuals also can have reeruptions and some may have shingles that never heals. Most people who get shingles reboost their immunity to VZV and will not get the disease for another few decades.
Youngsters whose mothers had chickenpox late in pregnancy, 5 to 21 days before giving birth,- or who had chickenpox in infancy, have an increased risk of pediatric shingles. Sometimes, these children are born with chickenpox or develop a typical case within a few days.
This answer is based on source information from National Institute of Neurological Disorders and Stroke.