Which describes a nomad? A. a person who has no settled home and moves from place to place
B. shared characteristics such as language, religion, and ancestry
C. a person who used to be a wanderer, but who has moved to the city
D. a community in which people own land as a group and live and work together

The constant presence of diseases or infectious agents within a given geographic area or population group. it may also refer to the usual prevalence of a given disease with such area or group. it includes holoendemic and hyperendemic diseases. a holoendemic disease is one for which a high prevalent level of infection begins early in life and affects most of the child population, leading to a state of equilibrium such that the adult population shows evidence of the disease much less commonly than do children (malaria in many communities is a holoendemic disease). a hyperendemic disease is one that is constantly present at a high incidence and/or prevalence rate and affects all groups equally. so probably family history.