Why the environment and environmental change matter to One Health


Submitted By: Meredith A. Barrett, Aaron H. Stoertz, Timothy A. Bouley


Human medicine and veterinary medicine demonstrate a long history of collaboration dating back to the 19th century.  Today, the One Health movement maintains this tradition, yet also increasingly incorporates environmental, public health, social science, public policy, and other non-medical scientific perspectives to address global health challenges.   Despite this shift towards multidisciplinarity, we feel that the emphasis on the environmental influences on human and animal health are not yet sufficiently represented in the movement. Though environmental issues are indeed finding a more prominent place in the One Health dialogue, they remain more on the fringes, likely as a result of the complexity in linking environmental changes to health. The following examples highlight the importance of the environment to One Health and illustrate how central One Health is and will be to global environmental change.

 It is essential to consider the environment in order to achieve optimal health for people and animals. In fact, addressing environmental factors affecting health is essentially a public health-oriented disease prevention strategy. Here are a few reasons why:

·          24% of the global burden of disease originate from environmental causes ( World Health Organization)

·          The potential health impacts of climate change will be broad and significant, including: heat and cold effects; wind, storms and floods; drought, nutrition and food security; food safety and disease; water and disease; air quality and disease; allergens and disease; vector and rodent-borne disease; occupational health; and UV radiation (Intergovernmental Panel on Climate Change)

·          More specifically, changes in temperature, precipitation and seasonality will influence infectious disease emergence, incidence and spread (e.g., dengue, malaria and cholera)

·          Other environmental drivers, such as land use changes and deforestation, also contribute to the loss of biodiversity and the spread of infectious diseases, as has been seen with malaria and Lyme disease

·          Human and animal well-being relies upon ecosystem services provided by the environment. Ecosystem services include supporting services (nutrient cycling, soil formation, primary production), regulating services (climate and flood regulation, disease buffering, water purification), provisioning services (food, water, fuel) and cultural services (aesthetic, spiritual, mental health) that make the persistence of human and animal life possible.  (See Figure 1 from the Millennium Ecosystem Assessment)

·          Many of these ecosystem services rely upon the maintenance of biodiversity (including species, ecosystems, populations and genes), which makes  possible the growth of food, healthy diets,  the development of new medicines, and the regulation of the emergence of infectious diseases  

 Despite the importance of the environment to the preservation of human and animal well-being, we face increasing challenges to the maintenance of healthy ecosystems. Rapidly shifting human pressures and global environmental change—including examples such as climate change, land use change, desertification and biodiversity loss—could severely compromise the future well-being of humans and animals. The global human population is estimated to reach 7 billion within the next few years and will increase its need for land, food and energy. However, currently 60% of the essential ecosystem services of the planet are degraded or are under increasing threat. This loss, combined with the potential increased frequency of heat waves, storm events, and droughts as a result of climate change, have the potential to contribute to global crop failures, soil erosion and, ultimately, injuries, malnutrition and other negative health outcomes.

 Human, animal and ecosystem health are inextricably connected. We see the One Health approach as an essential perspective to approaching these challenges. Collaboration among human health, animal health, public health and environmental science professionals will be necessary to address challenges, design collaborative solutions and create co-beneficial health and environmental policies for our rapidly changing world. The One Health Initiative can lead the way in further incorporating environmental programming into their mission and bringing more environmental professionals into the One Health movement.

The One Health Initiative website team is interested in increasing the presence of environmental professionals in One Health.  We have begun to solicit new articles with an environmental focus for the One Health Newsletter  If you work in health and the environment, please send us an email to see if you might be able to contribute an article to the One Health Initiative website and/or the quarterly newsletter c/o Editor Help us spread knowledge about these ecosystem connections. 

Figure 1. Harmful effects of ecosystem change on human health (from the Millennium Ecosystem Assessment “Ecosystems and Human Well-being: Health Synthesis;”

[Permission granted to reproduce World Health Organization item/s September 23, 2010 by WHO, Dolores Campanario, Geneva,Switzerland.]

To learn more, the following websites hold a wealth of information:

·          Millennium Ecosystem Assessment


·          Center for Global Health and the Environment


·          Center for Sustainability and the Global Environment


·          The World Health Organization

o          Climate Change and Human Health studies:

o         Health and Environment Linkages project :

o         Environmental burden of disease:

·          Intergovernmental Panel on Climate Change, Fourth Assessment Report, 2007, Human Health Chapter


·          IUCN Ecosystems and Human Wellbeing


·          UNEP and WHO’s Libreville Declaration on Health and Environment collaboration


·          Cooperation on Health and Biodiversity (COHAB)


·          Convention on Biological Diversity (CBD)


·          Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES)



 Meredith A. Barrett is a PhD candidate in the University Program in Ecology at the Nicholas School of Environment at Duke University, Durham, North Carolina (USA).  She is working to identify health consequences of human development on lemur populations in Madagascar.  Ms. Barrett, along with Aaron Stoertz, coordinate the Global Health Working Group, a student-run interdisciplinary forum at Duke University dedicated to educating students about global health issues.

 Aaron Stoertz is pursuing his MSc in Global health at Duke Global Health Institute and has a certificate in epidemiology from the University of North Carolina’s Gillings School of Global Public Health.  Mr. Stoertz’s current focus is human resources for health and health are distribution in underprivileged communities and nations.

 Timothy Bouley is currently studying global health adaptation to climate change while pursuing degrees in medicine at Duke University and environmental change at Oxford University, United Kingdom.