The paper describes the formation of a new scientific direction — molecular epidemiology. It shows the goals and main tasks of this direction, its significance for the development of fundamental and applied researches in different fields of medicine. The examples that reflect the role of molecular epidemiology in determination of molecular mechanisms of development of infection are represented. The attention is emphasized on necessity of careful planning of prospective molecular and epidemiological researches. The most common mistakes that can arise in the case of methodology ignoring epidemiology clinical are shown.
