‘One World One Health’ (OWOH), ‘One Medicine’ and ‘One Health’ are all injunctions to work across the domains of veterinary, human and environmental health. In large part they are institutional responses to growing concerns regarding shared health risks at the human, animal and environmental interfaces. Although these efforts to work across disciplinary boundaries are welcome, there are also risks in seeking unity, not least the tendency of one health visions to reduce diversity and to under-value the local, contingent and practical engagements that make health possible. This paper uses insights from Geography and Science and Technology Studies along with multi-sited and multi-species qualitative fieldwork on animal livestock and zoonotic influenzas in the UK, to highlight the importance of those practical engagements. After an introduction to one health, I argue that there is a tendency in OWOH visions to focus on contamination and transmission of pathogens rather than the socio-economic configuration of disease and health, and this tendency conforms to or performs what sociologist John Law calls a one world metaphysics. Following this, three related field cases are used to demonstrate that health is dependent upon a patchwork of practices, and is configured in practice by skilled people, animals, micro-organisms and their social relations. From surveillance for influenza viruses to tending animals, good health it turns out is dependent on an ability to construct common sense from a complex of signs, responses and actions. It takes, in other words, more than one world to make healthy outcomes. In light of this, the paper aims to, first, loosen any association between OWOH and a one world-ist metaphysics, and, second, to radicalize the inter-disciplinary foundations of OWOH by both widening the scope of disciplinarity as well as attending to how different knowledges are brought together.
