- By Dr. Trevor Hancock
- Professor and Senior Scholar
- School of Public Health and Social Policy
- University of Victoria
- British Columbia, Canada
- We need to be more assertive in stating that public health is by far the most complex, challenging, interesting and holistic specialty in the health sector.
- Public health is really a branch of human ecology, concerned with the health implications of the interactions of our culture and society with the built and natural environments.
- Not only are we highly urbanised, we spend the vast majority of our time indoors, so the built environment, as a setting where the physical and the social interact, is a large factor in determining our health.
- Nonetheless, we live 100 percent of the time within natural ecosystems on a small planet, and these natural systems – which are in decline – are the ultimate determinant of our health.
First, my sincere thanks for the honour you are bestowing on me, There is no greater honour than to be recognised by one’s peers, especially in another country, and especially by such a respected body as FPH. I have worked in public health for over 35 years, and plan to keep going until they nail down the lid of my coffin. Along the way I have learned a few things I would like to share.
Public health – the most complex specialty of all
First, health is almost entirely different from health care and medicine. While I graduated in medicine (from Bart’s), I sometimes tell medical students that I later graduated from medicine to health – and in the process, I had to un-learn medicine.
While medicine – and indeed, all the healing professions – are a noble cause, I truly believe that public health is a higher calling! Surely there are few jobs more important than keeping people healthy, protecting them from harm and preventing them from become sick or injured in the first place or dying prematurely.
Moreover – and this is something we seldom say, and not loudly enough – public health is by far the most complex, intellectually challenging and exciting of all the health professions. I like to tell medical students that by comparison with public health, neurology or heart surgery or other medical specialties are comparatively simple. Because in public health we not only need to know the biological and clinical sciences and epidemiology, we need to know ecology, urban planning, sanitary engineering, architecture, anthropology, sociology, community psychology, policy, planning, administration, communications, education, politics and more.
We need to extol the virtue of the generalist, or more precisely, the holist. Like society as a whole, we have failed to recognise that generalism or holism are in fact specialties in their own right, as are those that practice these ways of thought and action. Here I include the practitioners of family medicine as well as public health practitioners.
In fact, the multiple, complex and interacting ecological and social threats to health that we face in the 21st century cannot be solved by specialists, but by holists, who can see and recognise the patterns, understand and act on and within complex adaptive eco-social systems.
Public health as human ecology
Public health is really a subset within the discipline of human ecology – which was once wonderfully defined as “the study of the issues which lie at the interacting point of environment and culture” (Dansereau, 1966). It was the incorporation of these concepts in my work – as well as the thinking of mentors such as Harding LeRiche and John Last, who both wrote books on public health and human ecology – that led me to develop the Mandala of Health: A Model of the Human Ecososytem – together with my close friend and colleague Fran Perkins in Toronto in the early 1980s in Toronto (Hancock and Perkins, 1985; Hancock, 1985).
The socio-ecological approach embodied in this model has been core to all my work in public health, and should be core to the practice of public health at any level. Thus while much of my work in the past 40 years or more has been focused on the natural and built environments, it is important to understand that they both are eco-social systems.
We are now past the point at which more than half of humanity is urban, and in high and even many middle-income countries, that figure is 80 or even 90 percent. Moreover, we in the high-income countries spend about 90 percent of our time indoors. So the built environment is in many ways our most important environment.
But our cities and communities are in fact settings (as are our homes, schools, workplaces, hospitals, prisons and so on), which means they are places where the physical and the social environments intersect and interact. In fact, human ecology in part grew out of an attempt to understand cities in the 1930s. So the creation of healthy cities is an eco-social challenge.
However, while we may spend almost all of our time in built environments, we still live 100 percent of our time on the Earth, and within global and regional natural ecosystems. Those ecosystems are in trouble, and the cause is human activity. It’s not just climate change, bad though that is.
It’s also depletion of resources, especially those related to food production such as agricultural land and water; mounting damage to the oceans, which further threatens food supplies; the pollution of entire ecosystems and food chains – and ourselves – with persistent organic pollutants and heavy metals and – as result of all these and other changes – the start of a sixth great extinction, this one caused by us.
We are passing planetary boundaries for ecosystem stability in several key areas. But when ecosystems decline or collapse, so too do the communities and societies embedded within and dependent upon them.
All of these ecological changes – which are so massive and so significant that geologists are have been considering declaring a new era, the Anthropocene – constitute a massive threat to the health of the population – which means they are a public health issue, on a mammoth scale.
Public health must now adopt an eco-social approach in addressing the health implications of ecological decline (just as we did in addressing the health implications of industrialisation in the 19th century) in its task of creating a more just, sustainable and healthy future.
Public Health in the Anthropocene: Addressing the ecological determinants of health
While we have paid great attention to the social determinants of health in recent years, which I agree is important work, we have largely ignored these ecological determinants of health. That is why I have spent the past three years leading a workgroup for the Canadian Public Health Association examining the ecological determinants of health and the public health implications of global ecological change (the CPHA Discussion paper) and the 100 page technical report.
In our report we make it clear that the ecological and the social intersect and interact. The massive and rapid ecological changes we are seeing are driven by major social and economic forces which are themselves driven by social and cultural values rooted in Western notions of ‘modernization’, progress, development and growth. However, these driving forces contain within them the seeds of their own destruction. Clearly, we have to address them as a single eco-social problem.
In the 19th century, we confronted the massive challenge of industrialisation and urbanisation, and together with our reformist allies in many other sectors, we faced and largely dealt with that challenge. Of course, cities are still a challenge, especially the rapidly growing cities of the low and middle-income countries, so there is still much work to be done.
For the past 40 years the environmental movement has been doing public health’s job. Now we need to step up to the plate. We need to once again become leading players and partners in a process of reform, this time to create a more just, sustainable and healthy future for all. To do so we need to address both the urban health challenges and the global ecological changes we face.
We must educate the next generation of public health professionals in the context of human ecology and systems thinking, so they can take an eco-social approach to these massive challenges. Above all, we must become activists and advocates for economic, social, cultural and political changes that take us away from our present unhealthy course and that help steer us towards the more just, sustainable and healthy future we must create for future generations.
That is my challenge to the public health profession and to FPH. I hope you take it up.
Dansereau, P. (1966) 1st Commonwealth Human Ecology Council Conference, London.
Hancock, Trevor (1985) The mandala of health: a model of the human ecosystem Family and Community Health 8(3): 1-10.
Hancock, Trevor and Perkins, Fran (1985) The mandala of health: a conceptual model and teaching tool Health Education 24(1): 8-10.