Аннотация:The patterns and mechanisms of circulation of infectious agents in terrestrial and aquatic ecosystems are just beginning to be studied, because the attention of researchers has traditionally been focused on aboveground
ecosystems - natural focus zoonotic infections. Now, the specificity of the natural focus of sapronoses is becoming more and more important, above all - the ecology
of the challengers as full members of land and water communities. A wide perspective of field and experimental research in this relatively new direction of research on the problem of natural focus of infectious diseases opens up. The ability of pathogenic microorganisms to exist in water and soil and to reach
humans through the food chain, indicates that research on the circulation of pathogens in the environment is of great importance for human health.