One Health and the Evolving Discipline of Planetary Health
Human health and the state of our environment are inter-connected: the relationship is set out in the concepts of One Health and Planetary Health. WHO helps health professionals tackle such complex issues.
22 January 2017
In these notes I reflect on links between people’s health and the planet. I describe two different kinds of threat to health.
First: threats to health resulting from the degrading of the world’s natural ecosystems. The ways in which modern societies live have an increasing and direct impact on the natural ecosystems on which human life depends. Biodiversity, access to fresh water and forest cover are all diminishing. If these issues are not addressed quickly, life expectancy for millions of people in coming generations will decrease.
Second: threats to health resulting from discrete changes in the environments within which people live. In the year 2012, the unhealthiness of the places where people live resulted in 12.6 million deaths. Climate change will increase these risks: it is already impacting on people’s health and its impact is expected to increase in coming years. In addition, animals in the environment can be the source of illness. At least 75% of the emerging infectious diseases that have affected humans in the past decade have come from animals.
Interconnected and cross-sectoral approaches to human health are increasingly valued especially within communities and countries. Support for such approaches grows year on year.
The effort to improve people’s health by working at the interface between human, animal and environmental health was initially reflected in the One Health concept underpinned by the 12 Manhattan Principles. These were elaborated in September 2004, in New York, by an international group of strategic thinkers convened by the Wildlife Conservation Society. The principles proposed the adoption of a holistic approach to combat 'threats to the health of life on earth' under the banner 'One World, One Health’. They stressed the important linkages between the health of people and the environment and sustainable development. Other similar concepts have been developed – such as conservation medicine and ecohealth. In response to the threats posed by diseases that move from animals to humans (and vice versa) several nations have become actively engaged in what is now a movement for One Health that engages many different stakeholders and focuses on the sharing of experiences for greater impact.
More recently, Planetary Health (PH) was defined by a Rockefeller Foundation - Lancet Commission in 2015 as a discipline that enables health professionals better to understand these relationships between humans and their environments. PH is focused on the recognition that human health depends on natural systems, that natural systems are being degraded to an unprecedented extent and that these threats need to be addressed in a systematic way by multiple actors. The linkages are being documented and analyzed through cross-disciplinary science with a view to identifying specific determinants and assessing their contributions.
The proponents of PH recognize that new systems of governance - globally and nationally - may be needed to address these threats. They see a need for governance processes that encourage the development of interdisciplinary knowledge; the articulation of social, economic and environmental policies that are based on evidence; and cross-sectoral decision making that seeks – at all times - to safeguard the health of humans and the natural systems upon which we depend. As health professionals we must be concerned not just with the physical threats themselves but with providing sound evidence that can help influence political choices that can mitigate these threats.
Role of WHO
WHO has supported the implementation of One Health concepts through its engagement with other UN agencies, intergovernmental organizations and the Global Health Security Agenda. WHO is playing an important role when it comes to Planetary Health. WHO is encouraging research that helps ensure the linkage of policy choices to local realities and challenges faced by national governments. WHO support for PH can also strengthen the work being done under the umbrella of One Health and EcoHealth, enabling a range of different disciplines and sectors to move forward with robust and collective transformation in animal, human and environmental health.
Planetary Health offers multiple opportunities for calling to attention the interconnected determinants of illness and the significance of a multi-sectoral response as reflected in the 2030 Agenda for Sustainable Development. WHO has a key role in contributing to effective PH practice through structured processes for the convening of stakeholders at local, regional and national levels, and at specialized entities, development banks, and programmes within the international system. This is fully consistent with the One UN approach.
The discipline of Planetary Health involves work to reduce threats to human health, including some that are evolving over time. WHO will be expected to take a leading role in combating them. There are also evident linkages between PH issues and the standard-setting and technical work of WHO. Below I describe some examples of areas where WHO’s engagement is critical to the successful pursuit of PH and the broader concepts of One Health.
- Air pollution. Causes 7 million deaths annually and is often co-emitted with climate-pollutants and associated with deforestation. There is considerable global action in this space, e.g. Climate and Clean Air Coalition, Pollution Management and Environmental Health Trust Fund at the World Bank. WHO involvement remains important for linkages to Ministries of Health.
- Food and nutrition. Declines in wild fish and pollinators as well as heat and precipitation impacts of climate change will continue to unhinge healthy nutrition. WHO’s voice will continue to be critical in highlighting the link to chronic disease and ensuring food security.
- Infectious diseases. Vector-borne and water-borne disease are susceptible to climate/ecological impacts, urbanization, population changes, and travel – all relevant to the PH framework. WHO already contributes to efforts on biodiversity and health, which explore these links.
- Water scarcity. Affects food production systems and disease patterns. Also drives conflict resulting in mental health impacts and other broad health challenges. WHO can offer voice here to refocus natural resource discussions on health.
- Mental Health. Broadly impacted by any number of areas of environmental change – both local and global. It is important for WHO to address connections with other groups and agencies addressing environmental degradation. Environmental change is a major driver of displacement and migration, which affects conflict, disease, and ultimately mental health.
In coming years there will be more opportunities for WHO to refine its contributions to implementation of impactful actions in different areas of Planetary Health and One Health. Impact will depend, as always, on the relationships that can be built between WHO, governments and other actors.