In parallel to the advances in modern medicine, health sciences and public health policy, computer simulations and information technologies offer an important alternative for the understanding of disease transmission dynamics and epidemic patterns. During this talk, we will present the first steps required that may lead the design of epidemic models, i.e. the measure and the analysis of interactions within a closed socio-professional context. More precisely, this project was motivated by the study of the Health Care Workers (HCWs) exposure to tuberculosis in their work environment. In the health care context, if the tuberculosis transmission is globally controlled, the HCWs exposure remains obscure and individual factors associated to the contamination of HCWs in their work environment are not precisely known. Our study focus on the evaluation of the intensity and the frequency of contacts between patients and HCWs in a hospitak. To gather these interactions, we have chosen to dedicate a Wireless Sensor Network (WSN) inside a Service of Infectious and Tropical Diseases (Bichat-Claude Bernard Hospital, Paris) and a Service of Pneumology (La Pitié Salpétrière Hospital, Paris). Within the two services, each room has been equipped with a sensor node and each HCW carries an autonomous sensor during his presence in the service. An important characteristic of this measurement campaign is that it was performed in a closed environment, over a closed population and during a large continuous period of time. The result of this deployment is a huge and unique data set describing a complex dynamic interaction network.