Use of live phages for therapy on a background of coevolution of bacteria and phages

This article discusses the prospects and necessary preconditions for wide application of bacteriophages in therapy and prevention of infections. Standard procedures which are necessary to ensure of permanent and safe use of phage therapy everywhere for a long time are discussed. Special attention is given to consideration of principal differences in use of antibiotics and bacteriophages. This includes differences in a range of infections and pathogens, in methods of application, in the need for so-called preclinical testing for phages, in the regional character of phage therapy, in the necessity of organizing of a system for permanent estimation of the activity of phage preparations with purpose to bypass arising of phage resistant mutants. The possible negative role in use of live phages in veterinary and as antiseptics is also discussed. Some probable hypothetical scenarios as result of arising and mass accumulation of multiply phage-resistant pathogens are briefly discussed to stress the importance to remember in the process of usage of phage therapy about the critical role of phages in bacterial evolution.