RT Journal Article SR Electronic(1) A1 Earls, Megan R. A1 Steinig, Eike J. A1 Monecke, Stefan A1 Samaniego Castruita, José A. A1 Simbeck, Alexandra A1 Schneider-Brachert, Wulf A1 Vremerǎ, Teodora A1 Dorneanu, Olivia S. A1 Loncaric, Igor A1 Bes, Michèle A1 Lacoma, Alicia A1 Prat Aymerich, Cristina A1 Wernery, Ulrich A1 Armengol-Porta, Marc A1 Blomfeldt, Anita A1 Duchene, Sebastian A1 Bartels, Mette D. A1 Ehricht, Ralf A1 Coleman, David C.YR 2021 T1 Exploring the evolution and epidemiology of European CC1-MRSA-IV: tracking a multidrug-resistant community-associated meticillin-resistant Staphylococcus aureus clone JF Microbial Genomics, VO 7 IS 7 OP SP 000601 DO https://doi.org/10.1099/mgen.0.000601 PB Microbiology Society, SN 2057-5858, AB This study investigated the evolution and epidemiology of the community-associated and multidrug-resistant Staphylococcus aureus clone European CC1-MRSA-IV. Whole-genome sequences were obtained for 194 European CC1-MRSA-IV isolates (189 of human and 5 of animal origin) from 12 countries, and 10 meticillin-susceptible precursors (from North-Eastern Romania; all of human origin) of the clone. Phylogenetic analysis was performed using a maximum-likelihood approach, a time-measured phylogeny was reconstructed using Bayesian analysis, and in silico microarray genotyping was performed to identify resistance, virulence-associated and SCCmec (staphylococcal cassette chromosome mec) genes. Isolates were typically sequence type 1 (190/204) and spa type t127 (183/204). Bayesian analysis indicated that European CC1-MRSA-IV emerged in approximately 1995 before undergoing rapid expansion in the late 1990s and 2000s, while spreading throughout Europe and into the Middle East. Phylogenetic analysis revealed an unstructured meticillin-resistant S. aureus (MRSA) population, lacking significant geographical or temporal clusters. The MRSA were genotypically multidrug-resistant, consistently encoded seh, and intermittently (34/194) encoded an undisrupted hlb gene with concomitant absence of the lysogenic phage-encoded genes sak and scn. All MRSA also harboured a characteristic ~5350 nt insertion in SCCmec adjacent to orfX. Detailed demographic data from Denmark showed that there, the clone is typically (25/35) found in the community, and often (10/35) among individuals with links to South-Eastern Europe. This study elucidated the evolution and epidemiology of European CC1-MRSA-IV, which emerged from a meticillin-susceptible lineage prevalent in North-Eastern Romania before disseminating rapidly throughout Europe., UL https://www.microbiologyresearch.org/content/journal/mgen/10.1099/mgen.0.000601