This is a picture of herpes zoster (shingles) on the chest. Shingles are caused by the same virus that causes chickenpox. Outbreaks of shingles often follow the distribution of nerves in the skin. This distribution pattern is called a dermatome. The linear distribution of the nerve in the skin is very easily seen in this photograph.
Update Date 3/5/2014
Updated by: David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.