Public health as science was borne over a water pump and a cholera outbreak in London in the 1800’s, by pioneer Dr John Snow. Since those days, public health has evolved and advanced, and as society has changed so too has the health field that takes care of it.
About a decade ago, a group of public health experts in the UK began a thought experiment. They suggest that phases of health improvement can be thought of in metaphorical terms as a ‘wave’ and that we’ve experienced four waves so far, with a fifth wave of public health development required — one that will need to differ radically from the proceeding waves. They invited others to join them in envisioning what this might look like, furthering a conversation about the future of public health.
The underlying premise of this metaphor acknowledges that there are relationships between the waves of health improvement and that each is cumulative and interactive. This idea helps us envision change over time and how certain periods both create, and are grounded in, emerging ideas about society, health, and well-being. Primarily we must pay attention to our context and the systems in which we find ourselves or we will be ill-prepared to take care of communities, and society writ large. Though formulated in the UK, these ideas cross boundaries and can help our grounding in what is needed today, broadly as we strive for improvements in population health.
The Waves
The first wave stems from the Industrial Revolution. Public health challenges during this time, seen as moral problems, such as overcrowding, lack of clean water or sanitation, or poor nutrition created an environment for many forms of infection. The shift towards the use of science led to fundamental public health interventions focused on clean water, sanitation, and improvements in housing and living conditions.
The second wave stems from the strengthening of the appliance of science and a rise in scientific rationalism, whereby scientific discovery suggested new approaches based, for example, on the shift from miasmic to germ-based theories of disease. Breakthroughs in many fields, including medicine, occurred during this period.
The third wave was more grounded in the political realm, following the Second World War, and the idea that society is shaped by the structure of class relations, and health is the result of the conditions of everyday life. This led to the advent of the welfare state. Examples include welfare reforms such as social housing and benefits.
Organizations that delivered public health measures began to face increasingly complex challenges and a process of rapid change began. Many industrialized areas underwent a transition and more systems thinking emerged, and during the fourth wave the focus became on risk factors and lifestyle and the connections between factors like diet, exercise, and smoking and major disease patterns. Social inequalities began to be linked to health and the social determinants of health emerged.
Why This Matters
Despite all that they accomplish, current public health interventions are not solving many problems we face. Factors like population growth, energy use, environmental and economic stressors, and a widening gap of inequities are creating impossible exponential growth in a finite system. Change is inevitable. We must adapt.
Each wave describes advancements over time as a grounding for the next wave — the future of public health — and what thinking is needed to get us to a new way of knowing, understanding, and acting about health. As society faces new challenges, so too must responses adapt. Though this dialogue began before the pandemic, the principles can be broadly applied and we know more than ever from the last few years that an ability to maneuver, respond, and be flexible to the changing environment, emerging threats, and crises is required.
The Fifth Wave
The fifth wave envisions a public health system that advances active participation of the population as a whole, working together towards health as a common good. The focus is on inter-dependence and cooperation, a rebalancing of our mindset away from ‘anti’ (e.g. combating inequalities) to ‘pro’ (e.g. creating well-being), learning, and new orientations that combine objective (e.g. biomedical data) with subjective (e.g. lived experience) — and are grounded in an ecological model that considers the contexts in which we live, work, play, learn, and grow.
The principles underlay a ‘well-being system’ that is positive, holistic, proactive, promoting, innovative, responsive, and collaborative; a system in which we are gardeners, tending to the growth of what nourishes human life, spirit, and health creation. Overall, the fifth wave envisions a culture of health in a health-promoting society that by its nature is fair, just, and altruistic.
Today, we believe that our approach is tackling this fifth wave, and our work is grounded in these principles. We must work together to create a context in which health is promoted, people can thrive, there is a collective responsibility, we strive for well-being, we address inequities and determinants of health, think in an ecological way, and most importantly we focus on creating the healthy human. This is the way forward. This is the future. This is public health now.