[Analysis of the possible mechanisms of the action of socioeconomic factors on the epidemic process whose biological base is an open parasitic system].

The mechanism of action of socioeconomic factors on the epidemic process have been analyzed on the basis of the study of the influence, exerted on the biological properties of infective agents by environmental factors resulting from human activities, and the theory of the self-regulation of the parasitic system. Such mechanisms can be subdivided into the mechanisms affecting the epidemiological triad (the source of infection, the mechanism of transfer, and the susceptibility of the population) and the mechanisms facilitating the formation of infective agents with selective advantages (decreased virulence, resistance to antimicrobial preparations, etc.) under the influence of environmental factors resulting from human activities. The former mechanisms suppress and tend to localize the epidemic process, while the latter ones activate this process under the conditions becoming more complicated for the spread of the infective agent.