Whose health and which health? Two theoretical flaws in the One Health paradigm.

The One Health approach is a prominent paradigm for research and healthcare practice and increasingly applied in various fields. Theoretical and normative implications of the approach, however, remain underexposed so far, leading to conceptual incoherencies and uncertainties in the application of the concept. This article sheds light on two particularly influential theoretical flaws inherent to the One Health approach. The first difficulty relates to the question of whose health is considered in the One Health paradigm: humans and animals are obviously situated on a different level than the environment, so that the individual, population, and ecosystem dimensions need to be considered. The second theoretical flaw is related to the question of which concept of health can be meaningfully referred to when speaking of One Health. This problem is addressed by analyzing four key theoretical conceptions of health from the philosophy of medicine (well-being, natural functioning, capacity of achieving vital goals, and homeostasis and resilience) regarding their suitability for the aims of One Health initiatives. It appears that none of the concepts analyzed fully meets the demands of an equitable consideration of human, animal, and environmental health. Potential solutions lie in accepting that one concept of health is more appropriate for some entities than for others and/or forgoing the idea of a uniform conception of health. As a result of the analysis, the authors conclude that theoretical and normative assumptions underlying concrete One Health initiatives should be made more explicit.