Exploring the evolution and epidemiology of European CC1-MRSA-IV: tracking a multidrug-resistant community-associated meticillin-resistant Staphylococcus aureus clone
Megan R. Earls, Eike Steinig, Stefan Monecke, José Alfredo Samaniego Castruita, Alexandra Simbeck, Wulf Schneider‐Brachert, Teodora Vremeră, Olivia Dorneanu, Igor Loncaric, Michèle Bes, Alícia Lacoma, Cristina Prat, U. Wernery, Marc Armengol-Porta, Anita Blomfeldt, Sebastián Duchêne, Mette Damkjær Bartels, Ralf Ehricht, David C. Coleman
Abstract
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 SCC mec (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 SCC mec 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.