[General patterns of the functioning of parasitic systems (the mechanisms of self-regulation)]

Parasitic system is determined as a parasite's population in interaction with its natural habitat (host's population). Epidemiology, epizootiology and epiphitology as well as virology, microbiology, protozoology and helminthology study applied aspects of parasitic systems. The latter are characterized by four general principals determining selfregulation mechanisms of these systems: heterogeneity of interacting populations, their dynamic variability, phase functioning, dependence on conditions.