What is the difference between herpes zoster and varicella zoster virus?

Herpes zoster...: ...Is the return of the infection caused by the varicella zoster virus. The first time this infection occurs, it is called varicella.

Same virus, but: The first time a person catches the varicella zoster virus, he gets a case of chicken pox. Most of the time, chicken pox is obvious. Occasionally, a person has such a mild case, he doesn't know he has it. After chicken pox resolves, the virus lives (hides) in the nerves near the spinal cord. When it comes out and infects the skin again, the virus is called herpes zoster, and the rash is shingles.