An Extension of the Boundary Integral Method Applied to Periodic Disinfection of a Dynamic Biofilm

Several tolerance mechanisms have been introduced to explain how bacterial biofilms are protected from disinfection. One mechanism describes the transition between two subpopulations of bacteria, one of which consumes nutrients, divides, and is susceptible to antimicrobial agents. The other subpopulation consists of dormant bacteria that are insensitive to treatments. It has been shown that the presence of this persister subpopulation can explain experimental observations of bacterial tolerance, at least in simplified domains. This investigation describes the development of a two-dimensional model of an established biofilm immersed in a flowing bulk fluid, where the biofilm influences the fluid dynamics and where the fluid flow can deform the biofilm. We introduce several extensions to this model, including the reaction between the biofilm and the antimicrobial agent, bacterial and exo-polymeric substance production, and persister dynamics. The model and numerical methods are based on the boundary integra...

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