Age-Dependent Contact Patterns and Time Use Data

Emilio Zagheni, University of California, Berkeley
Piero Manfredi, Università di Pisa
Joel Mossong, Laboratoire National de Santé, Luxembourg

Social contact patterns are the critical explanatory factor of the spread of directly transmitted infectious diseases. Both indirect (via observed epidemiological data) and direct (via diaries that record ‘at risk’ contacts) approaches to the measurement of contacts by age have been proposed in the literature. In this paper we systematically discuss the possibilities offered by Time Use Surveys (TUS) for the estimation of contact patterns. TUS provide diary-structured data about the activities undertaken by sampled individuals and/or the locations where the activities occurred. Focusing on the notion of ‘mixing by activity/location and time slot’, we develop a methodology to estimate time of exposure contact matrices and mixing matrices. We provide estimates of these matrices with regard to the U.S. and we show that the allocation of time to activities is the major source of assortativeness of contact patterns by age.