Projecte final de Màster Oficial fet en col.laborció amb Universitat de Barcelona. Departament de Física Fonamental i Departament de Química Física.

English: We study the effect of coupling two random networks where an epidemic process propagates. A theoretical SIS model is applied and a new critical threshold for the existence of an endemic state is analytically calculated for the two coupled networks, under the assumption that there is total correlation between the outer degree and the inner degree of each node. Our main result is that a global endemic state can exist in the coupled networks, even though the epidemics does not propagate on each network separately. Finally, we checked these results by running large scale computer simulations.