The mechanism of parasite transmission as a tool of evolution and a criterion for a taxonomy of infectious disease

Abstract

This review discusses the principles of constructing epidemiological classifications of infectious diseases. A rationale is provided that taxonomy principles correspond to a combination of morphological and functional approaches. The former covers the shape and symmetry of parasites, while the latter is based on pathogen transmission mechanisms or the ‘function-and-energy’ approach. The idea that pathogen transmission mechanisms are an evolutionary tool implemented in the epidemic process is discussed. Transmission mechanisms are classified into those ensuring reproduction – hereditary, vertical, and contact, those supporting metabolic processes – necrophage, water-soil, and carnivorous for animal and plant infections, as well as those enabling transmission (for animals and humans) – fecal-oral and aerosol. As an example, a hypothetical model of the evolution of viruses based on their transmission mechanisms is substantiated.