What is this article about?
Shingles (also known as herpes zoster) is a viral infection caused by a reactivation of the varicella-zoster virus (VZV) that causes chickenpox (varicella). When someone first becomes infected with VZV, they will contract chickenpox. However, after chickenpox resolves, the virus will stay dormant in the dorsal root ganglia (nerve cells in the spine) and may reactivate later on in life. For this reason, only people who have had chickenpox are at risk of shingles. Shingles presents as a painful, blistering rash. The reactivated virus generally affects one or two adjacent dermatomes, which are areas of skin that are mostly supplied by a single nerve root branching out from the spinal cord.