Horizon 1 1 17 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES Acta Biotheoretica 75-86 SIRS model two patch system linear chain of patches fast migration aggregation of variables basic reproduction rate individual based model multi agent simulations 2008 fdi:010042615 ENG Acta Biotheoretica 0001-5342 CC:0002563379-0005 1-2 10.1007/s10441-008-9036-y https://www.documentation.ird.fr/hor/fdi:010042615 https://www.documentation.ird.fr/intranet/publi/2008/06/010042615.pdf 56 Horizon (IRD) We consider a two-patch epidemiological system where individuals can move from one patch to another, and local interactions between the individuals within a patch are governed by the classical SIRS model. When the time-scale associated with migration is much smaller than the time-scale associated with infection, aggregation methods can be used to simplify the initial complete model formulated as a system of ordinary differential equations. Analysis of the aggregated model then shows that the two-patch basic reproduction rate is smaller than the 1 patch one. We extend this result to a linear chain of P patches (P > 2). These results are illustrated by some examples for which numerical integration of the system of ordinary differential equations is performed. Simulations of an individual based model implemented with a multi-agent system are also carried out. 050 ; 020