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PhD defense - Loïc Marrec
23
JUN 2020

I am pleased to announce that I will defend my thesis this Tuesday, June 23rd at 2:30 pm.

It will take place by videoconference and will be webcast live at https://www.twitch.tv/kevinberlemont (no registration required; thanks to Kevin Berlemont for logistical support).

My defense, which will be in French, is about: Modelling the evolution and spread of antimicrobial resistance.

The members of the jury are:

- Guillaume Achaz, Referee

- Luis-Miguel Chevin, Referee

- Florence Débarre, Examiner

- Bahram Hushmandzadeh, Examiner

- Annick Lesne, Examiner

- Raphaël Voituriez, Thesis Director

- Anne-Florence Bitbol, Guest

The summary:

Understanding the evolution of antimicrobial resistance in a host and its spread in a host population is of paramount importance in addressing this major public health problem. In this thesis, we focus on the impacts of environmental variability and population structure on the evolution of resistance in a microbial population, as well as its spread in a host population. More specifically, we address these issues by developing stochastic theoretical models and using methods inspired by out-of-equilibrium statistical physics. In the first part, we study the emergence of resistance in fixed and variable-size microbial populations undergoing periodic antimicrobial treatments. We then look at the evolutionary rescue by mutants of a microbial population destined for extinction in an environment that progressively degrades, for example in the presence of increasing antimicrobial concentration. In the second part, we address the impact of population structure on evolution by introducing a new model that generalizes existing models, which will allow us in the future to study the evolution of antimicrobial resistance in subdivided microbial populations. Finally, we examine the spread of antimicrobial resistance in a host population, incorporating immunity induced structural effects.