Epidemiologic aspects of ecology of foodborne infection causative agents that have taken root in contemporary technogenic loci created by humans in urbocenoses which include agrocomplexes of animal breeding, vegetable growing in open and closed ground are discussed. Soil and water sources with a wide transport network where microorganisms dwell in the environment under favorable for vital functions and growth conditions (humus deposits, temperature regimen, optimal pH, associations with hydrobionts, biofilm formation) are potent secondary reservoirs of infection causative agents. Some molecular-genetic mechanisms of polyhostality of Gram negative bacteria and listeria are examined.