Management of infectious wildlife diseases: bridging conventional and bioeconomic approaches

The primary goal of disease ecology is to understand disease systems and then use this information to inform management. The purpose of this paper is to show that conventional disease ecology models are limited in their ability to inform management of systems that are already infected, and to show how such models can be integrated with economic decision models to improve upon management recommendations. Management strategies based solely on disease ecology entail managing infected host populations or reservoir populations below a threshold value based on R(0), the basic reproductive ratio of the pathogen, or a multiple-host version of this metric. These metrics measure a pathogen's ability to invade uninfected systems and do not account for postinfection dynamics. Once a pathogen has invaded a population, alternative management criteria are needed. Bioeconomic modeling offers a useful alternative approach to developing management criteria and facilitates the consideration of ecological-economic trade-offs so that diseases are managed in a cost-effective manner. The threshold concept takes on a more profound role under a bioeconomic paradigm: rather than unilaterally determining disease control choices, thresholds inform control choices and are influenced by them.