Should someone who has been diagnosed with the zoster virus and is only 23 get the zoster vacation?

Probably yes: Herpes zoster (shingles) is not only a problem in older persons; it's less common at your age, but not rare. It usually does not indicate any problem with the immune system unless it occurs repeatedly. Although the vaccine aginst varicella zoster virus (VZV) is mostly recommended over age 50, it probably makes sense in anyone with a first episode of shingles. Discuss with your doctor.