for socio-economic and community development; water access and water rights (particularly for the poor); public or private exploitation of water for economic gains through dams, reservoirs and hydroelectric power; upstream-downstream equity issues; spatio-temporal variability.
The Watershed Governance Prism and other conceptual models of environment and health promote a holistic and synthetic approach to complement the normal scientific and social science tools that we can bring to bear on environment-and-health issues. This highlights the necessity for inter- and trans-disciplinarity in addressing such problems. The term ‘governance’ also points to the need for collaborative and participatory approaches in the understanding and management of health and well-being as emergent properties of complex and coupled human and natural systems.
Another way (apart from defining organizational or geographic units) to manage the challenging process of doing ecohealth work has been to define basic principles. Dominique Charron from Canada’s IDRC articulated six key principles or guiding considerations (Charron, 2012). These principles echo the ecohealth approach and conception of health presented above. They include:
• systems thinking;
• transdisciplinary research (i.e. research that engages community members and not just scholars) (Berger-González et al., Chapter 6, this volume);
• participation (which is an extension and elaboration of trandisciplinarity);
• ecological sustainability;
• gender and social equity; and
• knowledge-to-action.
Of course, each problematic environment-and-health situation in which we might intervene is unique. Thus, different applications of the ecohealth approach emphasize these principles to different extents and use a wide variety of ways to mobilize these principles. For example, over 5 years, the Dahdaleh Institute for Global Health Research at York University will draw upon complex adaptive systems theory and employ agent-based modelling, developing scenarios to understand climate change impacts and human health in the Chilwa Basin of Malawi. Partnered with Dignitas International and local communities, they are building capacity to understand interactions of extreme weather, ecological services, infectious diseases, food security, clinical public health and disaster risk management to target deficits in ecological services management and clinical and population health interventions (J. Orbinski, 2019, unpublished data). While connecting with all six principles of the ecohealth approach, the systems thinking principle is formally and strongly emphasized in this project.
Waleckx et al. (2015) on the other hand, in their approach to managing Chagas disease in the Yucatan, dealt with systems less formally, mobilizing community knowledge to identify interrelated behaviours, knowledge, attitudes and perceptions of community members, along with environmental factors to inform interventions. They operated an iterative process with local government, social workers, community members, carpenters, the health centre and the research team, in which they explored and agreed upon strategies for intervention. Each stakeholder played a different role in the process, which involved interventions such as installation of window screens and education about cleaning of chicken coops. This project strongly emphasized the transdisciplinary and participation principles.
Another example involving ‘complex adaptive systems’ is offered by an ecohealth project in Chennai, India (Bunch et al., 2005, 2006, 2019; Kumaran et al., 2012). In this project researchers partnered with community members in low-income squatter settlements (‘slums’). Participating communities were formally conceived as ‘social-ecological systems’ that were characterized by recurring outbreaks of cholera and other disease, inadequate solid waste disposal, poor or absent toilet and sewerage facilities, poverty, malnutrition, low levels of literacy, poor access to potable water, and child labour. They faced continued pressures of the caste system, urbanization, political conflict and lack of tenure; they were stuck in a resilient (maladaptive) poverty trap. The partnership worked to build community capacity to manage this situation and improve human well-being. This project looked less to the natural environment and ecological sustainability than did the previous examples, but emphasized gender and social equity more strongly, along with participation and systems thinking.
In these projects and others, given the strong resistance of certain populations to global health and animal health interventions, the involvement of stakeholders and sharing of knowledge as it emerges have been demonstrated repeatedly to be essential not just to generate knowledge (i.e. from a PNS perspective), but also to implement effective programmes.
Future Directions for Ecohealth
Ecohealth and One Health as currently defined are relatively new fields, and the feedback loops between practice and theory are still influencing each other, resulting in both richer theory and more effective practice. Some recent explicitly ‘ecohealth’ research initiatives include projects working with communities to understand and facilitate responses to climate change in equatorial Africa, Canada’s far north and the Peruvian Amazon, connecting conservation and human well-being in Costa Rica, studies on mercury dynamics in the Brazilian Amazon, social-ecological impacts of Agent Orange in Vietnam, and development of interactive, open-source teaching materials in Canada, Africa, Asia and Latin America.
In the realm of One Health, initiatives assume particular goals such as eradication or management of zoonotic and other animal-related diseases. In these cases, clear goals can be set, programmes undertaken, results achieved with some predictability, and the value-added benefit of joint human-animal strategies calculated. In the long run, however, One Health activities will need to be understood in a context of global social-ecological changes, where outcomes are less certain (Zinsstag et al., 2011).
A current example of what can occur when normal, linear science is applied to managing complex systems emerged in late 2019 and early 2020. In 2019, more than 200 million pigs in China died from – or were killed to ‘stamp out’ – African swine fever (ASV). That was about half of the pigs in China and a quarter of all the pigs in the world. In late 2019 and early 2020, hundreds of millions of Chinese people were in markets and malls searching for scarce meat to celebrate the end of the lunar ‘Year of the Pig’ and launch the ‘Year of the Rat’.
While pigs were in short supply, the Huanan Seafood Market in Wuhan, Hubei Province, China, was well stocked with other species to help their customers stock up for the celebrations. These included peacocks, wild rabbits, snakes, deer, crocodiles, turkeys, swans, kangaroos, squirrels, snails, foxes, pheasants, civets, ostriches, camels, cicadas, frogs, roosters, doves, centipedes, hedgehogs
