Modelling of epidemics spreading through animal trade networks accounting for farmers’ decision making. Assessment of control strategies for enzootic diseases

Effective control of livestock diseases, mainly spreading through animal trade, is a major issue for sustainable animal farming and competitive agri-food chains, as well as for public health. Preventing outbreaks and lowering prevalence or eradicating diseases call for improving current control methods, control scheme organization, and actors’ compliance, in particular for unregulated diseases for which control related decisions are left to collectively local and/or individual initiatives. A growing concern is the interdisciplinarity between economics and epidemiology, for which scientific developments are expected to bring groundbreaking insight in field applications of infectious disease management. In this context, there is a need for integrative models combining dynamics of the contact network between farms, epidemic processes unfolding on these networks and farmers’ behavior with respect to animal trade and implementation of control measures. These models are powerful tools complementary to field and experimental data and expertise, contributing to help guiding management of animal health at various organization levels and temporal and spatial scales.

The PhD will aim at assessing the impact of control strategies on the spread of enzootic pathogens, when accounting for farmers’ decision making as regards animal trade and health management. Mechanistic dynamic models incorporating movements of animals between farms, epidemiological within-herd dynamics and farmers’ decision making will be elaborated. This modeling approach will not only include epidemiological features but also health management variables derived from economic trade-offs at the farm level and feedback loops between epidemiological dynamics and farmers’ individual on-farm practices. The modeling approach will be designed for cattle enzootic diseases such as paratuberculosis or bovine viral diarrhea virus.