Causes of Shingles
Shingles is caused by the reactivation of a dormant varicella-zoster virus (VZV). It cannot be acquired from another person.
While shingles can occur at any age, more than two-thirds of cases occur in people over the age of 50. Shingles is 20 to 100 times more common in immune compromised individuals, such as people with HIV, the elderly, and those whose immune systems are suppressed by medication or chemotherapy.
A person who has never had chickenpox could develop the infection by coming into contact with shingles blisters.