Analysis of methicillin resistant Staphylococcus aureus strains from Czech Republic and Slovakia

Methicillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen that has spread into the community since the 90s. In general, the community-associated (CA- MRSA) strains are more virulent, but less resistant to antimicrobials than the hospital- acquired strains (HA-MRSA). Some lineages of MRSA such as sequence type 8 have been transmitted more successfully around the world than others and there are situations where a dominant lineage has been replaced by a new one. The factors that are crucial for the selection of dominant lineage are often not clear. As part of this thesis, a longitudinal study of MRSA epidemiology in the Motol University Hospital during the period of 2018-2020 was performed and the occurrence of MRSA clonal complexes was characterized. A multicenter study of the epidemiological situation of MRSA in Slovakia during the period of January - April 2020 was also performed concomitantly. Moreover, several isolates from dominant lineages were further characterized by their phenotype. In the Motol University Hospital study, it was found that the HA-MRSA of the clonal complex 5 dominates and is represented mainly by spa-type t586; a finding that concurs with recent studies from the Czech Republic. In Slovakia, similar to the Czech Republic, MRSA lineages from clonal..