Most of the extremely contagious infectious diseases in recent memory have emerged first amongst animals before making the leap to humans. These zoonotic diseases, including Ebola, Avian flu, the Nipah virus and severe acute respiratory syndrome (SARS) have come with a collective death toll in the hundreds of thousands, whilst it remains unknown how extensively this tally will change by the time COVID-19 has run its course.
The economic and social disruption that these viruses have caused has been immense – in six months, SARS cost an estimated $40 billion worldwide (1), whilst the cost of COVID-19 is already measured in the trillions (2). Worse still, unless human activities related to travel, agriculture, land use and trade radically change, it seems likely that we will be footing the bill for zoonotic disease on an increasingly regular basis (3). Ending the habits of a generation can’t be done overnight, however. How, then, do we go about addressing the rise of zoonotic diseases?
In 2004, the Wildlife Conservation Society (WCS) invited health experts from around the world to discuss the interrelated nature of animal, human and environmental health. The 12 ‘Manhattan Principles’ that emerged – advocating for interdisciplinary and holistic public health interventions and research - served as the roadmap for the ‘One Health’ approach that is building momentum today (4).
One Health is defined by The One Health Commission as ‘a collaborative, multisectoral, and trans-disciplinary approach - working at local, regional, national, and global levels - to achieve optimal health and well-being outcomes recognizing the interconnections between people, animals, plants and their shared environment.’ It has been applied successfully to improve understanding of - and responses to - a wide range of health hazards (5).
Given that the combined arms approach of One Health has been proven to provide a more effective response to outbreaks than siloed alternatives, why is it not being used all the time and how do we encourage its uptake as a mainstream approach?
One problem is the fact that there is, for the most part, just not that much communication and collaboration between the various scientific disciplines. Hopefully, this will change in the future as more institutions and their students see the value in cross-sectoral learning. Some have already begun: UCL currently offers graduate research scholarships for cross-disciplinary training, whilst the INDOHUN network of higher education institutions works specifically towards promoting One Health. These are just two examples of institutions that are training their public health researchers to consider holistic approaches from the earliest stages of their careers.
However, such progress cannot be contained to places of learning: national and international collaborative networks are needed to bring this approach to the field and sophisticated monitoring systems need to be developed to observe new patterns in animal, human, microbial and plant populations and how said patterns might be interlinked. These systems will enable early detection of potential threats and facilitate rapid reaction to them.
A number of regulatory and oversight changes will have to be made to facilitate this level of open scientific inquiry and cross-disciplinary learning. Authority over these different fields cannot remain so strictly divided, there must be better interface and cooperation between gatekeepers, all of which should be informed by robust scientific evidence. Greater cooperation is needed between governments and scientific bodies internationally so that, in times of crisis, there already exists a communication framework that can facilitate a coordinated, One Health response (6).
It is important to note that tackling zoonotic disease is just one use case for the One Health approach; it has immense value for many of the future health challenges we will face, most notably antimicrobial resistance and climate change. Antimicrobial resistance will necessitate the development of new treatments, but prevention will become ever more important; this will require greater understanding of the links between human, animal and environmental health. Climate change will also disrupt health infrastructures and systems across many, if not all, countries. The displacement of populations and the ecological and environmental changes that climate change will bring about will require One Health inspired solutions. Health systems that consider One Health relationships will be most robust to the impacts of our changing climate.
In conclusion, a One Health approach will become increasingly essential in the decades to come, simply as a result of changes to our world. If we promote and invest in One Health now, it is clear will be in far better shape to fend off the health threats of the future.
Here at Aceso, we practice what we preach; our firm belief in the value of the One Health approach has been actioned within our Childhood Infections and Pollution (CHIP) Consortium. One Health and participatory research is helping to identify sources of AMR and pollution-related infections amongst children under 5 residing in peri-urban slums. We are proud to partner with UCL, INDOHUN and all the other consortium members to work to improve the lives of these children and to identify infrastructural and behavioural solutions to these One Health contributors to disease.
Kissoon N., The threat of severe acute respiratory syndrome (SARS). West Indian Medical Journal. 2003 Jun;52(2):91-4. PMID: 12974057.
Simon Freeman, £5 trillion: how much the Covid-19 pandemic cost the global economy in 2020 Evening Standard. [External Link] Published 24th December 2020. Accessed 7th January 2021.
Review of: Lederberg J., Shope R.E., Oaks S.C., eds. Emerging Infections: Microbial Threats to the United States. Washington, DC, USA: National Academies Press; 1992. [External Link] Accessed 7th January 2021.
Cook R.A., Karesh W.B., Osofsky S.A., About “One World, One Health”. One World, One Health. [External Link] Published 2009. Accessed 7th January 2021.
One Health Commission., What is One Health? One Health Commission. [External Link] Updated 2021. Accessed 7th January 2021.
Destoumieux-Garzón D., Mavingui P., Boetsch G., The One Health Concept: 10 Years Old and a Long Road Ahead. Frontiers in Vetinary Science. (2018);5(1) [External Link] Accessed 7th January 2021.