and medicine (Kaplan, 1966; Green, 1998; Beinart and Brown, 2013). The influence of these experiences and contexts can, for example, be detected in Calvin Schwabe’s frequently cited work, Veterinary Medicine and Human Health (Schwabe, 1964, 1969, 1984). More generally, this history indicates that many of the roots of present-day One Health lie in earlier currents of veterinary thought and practice that were deeply entangled with projects of development, international health, aid and post-colonial reconstruction.
Conclusion: From One Medicine to One Health
In analysing the changing relations between the health of humans, animals and the environment, this chapter demonstrates the many and varied links between them. Human medicine, in particular, has a rich history of engagement with animals, their diseases, and the people and institutions dedicated to animal health. Correspondingly, since the late 18th-century creation of their profession, vets have supported, collaborated and sometimes competed with this medical programme. These interconnections can be explained, in part, by reference to prevailing scientific ideas, practices and disease problems, but they can only be fully understood by examining the people involved, their institutional settings, and the wider professional, political, economic and environmental contexts. The historical specificity of these factors, as well as the variability of the health activities they influenced, makes it impossible to construct a simple, linear narrative linking past to present. Nor is it possible to draw direct lessons from history, or to claim – as do many existing histories – that the work of certain historical figures demonstrates the importance of pursuing One Health today.
This does not mean, however, that the past is irrelevant to the present. One key finding to emerge from this account is that links between the health of humans, animals and the environment were often investigated at grass-roots levels in the course of everyday veterinary and medical science and practice. For the most part, these activities were not articulated into a definite agenda of ‘comparative pathology’, ‘comparative medicine’, ‘veterinary public health’ or ‘One Medicine’. Only at certain historical junctures did practitioners choose to adopt these terms, usually in order to validate or win wider support for operationalizing their activities. Pushing beyond these labels and the rhetoric that surrounded them and looking at what was actually happening on the ground reveals that integrated approaches to health were much more widespread and more significant than previously realized. It is no understatement to say that health and medicine today are heavily shaped and underpinned by the many precursors to One Health.
One Health itself, as a self-consciously labelled set of activities and agendas, has emerged very recently out of a complex and rapidly shifting coalition of international health bodies, veterinary associations, academic advocates, environmental organizations and pharmaceutical companies. While its history has been fully explored elsewhere (e.g. Lebouf, 2011; Chien, 2013; A. Cassidy, 2019, unpublished), this chapter concludes by sketching out the broad contours of these developments in order to put the rest of this volume into context.
During the 2000s, elements of the ongoing traditions of comparative medicine and VPH came together into a rearticulated vision of ‘One Medicine, One Health’. This involved the alliance or convergence of veterinary and human medical research and/or clinical practice, including collaborative research, and shared clinics, vaccination strategies, equipment and drug development (e.g. King et al., 2008). In parallel, a different (albeit overlapping) set of actors and agendas came together around the term ‘One World, One Health’TM (OWOH). In contrast to the veterinary–medical focus of One Medicine, OWOH tended to address a broader range of disciplines across the life and environmental sciences while maintaining a relatively tight focus on issues such as ‘emerging infectious diseases’. The idea of ‘One World’ (OW) has its origins in mid-20th-century debates about international relations and the formation of the United Nations Educational, Scientific and Cultural Organization (UNESCO) (Sluga, 2010). It was significantly taken up by health actors during the 1990s, when the global scale and potential wildlife origins of the human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) pandemic were recognized (Whiteside, 1996; King, 2004). In 2004, the first of a series of meetings between human public health, conservation and infectious disease experts was organized by the US-based Wildlife Conservation Society on the theme of OWOH. The idea then found strong purchase in international responses to the outbreak of highly pathogenic avian influenza (HPAI), and was adopted by the WHO, FAO, OIE and others in a shared statement of cooperative intent (FAO et al., 2008) following the HPAI crisis (Scoones and Forster, 2008; Scoones, 2010).
Through the 2000s, these two sets of agendas became increasingly intertwined, and since the end of the decade they have increasingly shared the broader, snappier and more widely used banner of ‘One Health’ (Zinsstag et al., 2005; FAO et al., 2010). The recent adoption of the language of One Health by key organizations across the worlds of veterinary and human medicine, international health and other agencies, national governments and research funding bodies, represents the integration of these various agendas. Advocates, based particularly in the USA and Switzerland, have organized workshops, conferences, reports, websites and journal publications to promote it. As an organizing concept, it has proved flexible enough to encompass very different languages, ideas and working practices, yet coherent enough to enable communication across disciplinary and organizational divides (Lebouef, 2011; Chien, 2013). However, questions remain about the long-term viability, practical utility, sustained interdisciplinarity and persistent anthropocentrism of One Health (Lee and Brumme, 2013; Bardosh, 2016; Cassidy, 2016; Manlove et al., 2016; Kamenshchikova, 2019), as well as how it can productively engage with questions of colonial and post-colonial legacies, power, and ongoing tensions between local and ‘global’ approaches to health (Scoones, 2010; Green, 2012; Beinart and Brown, 2013; Yates-Doerr, 2015; Cunningham et al., 2017; Rock et al., 2017).
Like its predecessors, the rise of One Health cannot be explained solely by advocacy, internal scientific logic, or as the natural and inevitable outcome of long-standing efforts to bring humans, animals and the environment closer together. A product of 21st-century concerns, it forms part of a wider cluster of research and policy agendas, including ‘food security’, ‘biosecurity’, ‘global health’ and ‘translational medicine’, which also aim to break down barriers between disciplines. Intriguingly, each of these addresses issues relevant to, or even overlapping with One Health, but is oriented towards a different group of disciplines (e.g. ‘food security’ tends to appear in the environmental and
