No, they don't spread like that. They follow a nerve band.
The word "shingles" means zone or band. Shingles is a viral infection of a nerve and corresponding skin band overlying the nerve. The distribution of the skin lesions follows the nerve. The skin lesions are characterized by small blisters filled with pale tan fluid surrounded by redness. The skin eruption develops in an area of pain and discomfort which precedes the eruption by about three to seven days.
Shingles represents an acute reactivation of an infection by the chickenpox virus or Varicella. Since the primary attack of chickenpox, the virus has remained dormant in the sensory nerve center or ganglion.
I had them about 2+ years ago. They lasted about 3 weeks. My doctor told me they go away on their own. He said that they have treatments to help some, but no "cure." He had some concern because one blister was close to my eye, but since the blister was already drying up, no treatment was done.