The basic mechanisms of the formation of epidemically significant nosocomial bacterial clones

Russian and foreign research on specific characteristics of bacteria that can cause infections associated with the provision of health care, the molecular genetic markers of these bacteria, and the basic mechanisms of the formation of epidemiologically significant nosocomial bacterial clones are reviewed in the present article. It is shown that the main characteristics of nosocomial clones, such as resistance to multiple antimicrobial drugs, genome plasticity, the ability of pathogens to form biofilms, and the presence of virulence factors, are apparently common for all bacterial species. Microevolution processes, including mutations, genomic rearrangements, and horizontal gene transfer, underlie the formation of nosocomial bacterial clones. These processes provide bacteria with selective advantages under certain conditions and thus enable the emergence of epidemics. Keywords: healthcare-associated