occurs in establishment of localization host establishment of localization in host Albert Goldfain An establishment of localization process in which a material entity reaches a site in an organism in which it can survive, grow, multiply, or mature. Lindsay Cowell Alexander Diehl Requested addition of this term to the GO. An organism begins bearing a particular host role as soon as the extended organism contains the relevant material entity, regardless of that entity's location in the extended organism. An establishment process is any process by which the entity reaches a location in the extended organism in which it can persist and continue its lifecycle. For example, an organism is host to a virus as soon as any part of the extended organism is occupied by virus particles. During an establishment process, virus particles enter host cells of the relevant type, and viral DNA is integrated into host DNA.