Random Modelling of Contagious (Social and Infectious) Diseases: Examples of Obesity and HIV and Perspectives Using Social Networks

Modelling contagious diseases needs to incorporate in the models information about social networks through which the disease spreads out as well as data about demographic and genetic changes in the susceptible population, and also to include mechanistic knowledge about contacts between hosts and pathogens. We will introduce all these elements in two examples of contagious diseases, the obesity, a social pathology partly caused by behaviour mimicking some dominant habits of nutrition and HIV transmitted through social networks. Obesity spread modelling will use the notion of homophilic graphs and we will show that a micro-simulation of IBM type (Individual Based Modelling) can reproduce the current stable incidence of the HIV epidemic in a population of HIV-positive MSM (Men having Sex with Men).