Administrative Data to Explore the Role of Family History as a Risk Factor for Herpes Zoster.

We used administrative data to study the impact of family history on the risk of herpes zoster (HZ). Our HZ cases and our HZ family history were both ascertained on the basis of medically attended diagnoses, without reliance on self-report or recall bias. Family history was associated with HZ risk among both siblings and parents. The strength of the association differed when the index child was latently infected with vaccine-strain vs wild-type varicella zoster virus.