The microevolution of the highly clonal monophasic Salmonella Typhimurium circulating in Europe since 1992 have been progressed. Phylogeny, presence of specific genomic sequences and Bayesian evolutionary analyses have been conduced to understand the high fitness and the evolution of this hazardous Salmonella. This work is part of a collaborative study (ANSES, AHPA, SSI, Bfr, RKI, UNIBO and Ifremer) progressed within the ‘COllaborative Management Platform for detection and Analyses of (Re-) emerging and foodborne outbreaks in Europe’ (COMPARE) project which has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under Grant Agreement No. 643476.. Microevolution study of monophasic Salmonella Typhimurium circulating in Europe

A microevolution study on the highly clonal monophasic Salmonella Typhimurium circulating massively in Europe since 2010 have been progressed on 300 genomes of Salmonella Typhimurium and its monophasic variant isolated from 1992 to 2018 from 5 countries (UK, FR, IT, DE, and DK). The phylogeny and presence of specific genomic regions (i.e. Salmonella pathogenic island, fljB region, …), of genes associated to antimicrobial and heavy metals resistance and of plasmids have been investigated to understand the fast spreading of this hazardous Salmonella. Comparatives phylogeny and Bayesian evolutionary analyses have been conduced to investigate the possible co-evolution between these regions and determine the timeframe of their acquisition.