Listeria monocytogenes (Lm) is a major human foodborne pathogen. Numerous Lm outbreaks have been reported worldwide and associated with a high case fatality rate, reinforcing the need for strongly coordinated surveillance and outbreak control. We developed a universally applicable genome-wide strain genotyping approach and investigated the population diversity of Lm using 1,696 isolates from diverse sources and geographical locations. We define, with unprecedented precision, the population structure of Lm, demonstrate the occurrence of international circulation of strains and reveal the extent of heterogeneity in virulence and stress resistance genomic features among clinical and food isolates. Using historical isolates, we show that the evolutionary rate of Lm from lineage I and lineage II is low (∼2.5 × 10-7 substitutions per site per year, as inferred from the core genome) and that major sublineages (corresponding to so-called "epidemic clones') are estimated to be at least 50-150 years old. This work demonstrates the urgent need to monitor Lm strains at the global level and provides the unified approach needed for global harmonization of Lm genome-based typing and population biology.
Auteur : Moura Alexandra, Criscuolo Alexis, Pouseele Hannes, Maury Mylene M, Leclercq Alexandre, Tarr Cheryl, Bjorkman Jonas T, Dallman Timothy, Reimer Aleisha, Enouf Vincent, Larsonneur Elise, Carleton Heather, Bracq-Dieye Helene, Katz Lee S, Jones Louis, Touchon Marie, Tourdjman Mathieu, Walker Matthew, Stroika Steven, Cantinelli Thomas, Chenal-Francisque Viviane, Kucerova Zuzana, Rocha Eduardo P C, Nadon Celine, Grant Kathie, Nielsen Eva M, Pot Bruno, Gerner-Smidt Peter, Lecuit Marc, Brisse Sylvain
Nature Microbiology, 2016, vol. 2, p. 1-10