Whoever would study medicine aright must learn of the following subjects. First he must consider the effect of the seasons of the year and the differences between them. Secondly he must study the warm and the cold winds, both those which are in common to every country and those peculiar to a particular locality. Lastly, the effect of water on health must not be forgotten.
-On Air Water and Places, by Hippocrates.
Every year thousands of students enter college and graduate programs in medicine, nursing, allied health and public health. As we move into the 21st century, it is imperative that health program curricula incorporate education on issues of sustainability as an integrated part of training for future health care providers.
We live in a world with enormous environmental challenges, including unsustainable population growth, global climate change, and shortages of food, water, and fuel. How do such challenges impact the work of health providers? The World Health Organization (WHO, 2006) estimates that 13 million deaths annually are attributed to preventable environmental causes, representing 23% of all premature mortality. In addition, the environmental burden of disease falls disproportionately on the poor (WHO, 2006). Environmental sustainability is inherently linked and inseparable from global health and human rights.
More than twenty years ago, King (1990) stated that health, itself, is by definition, a sustainable state. The corollary is also true: unacceptable use of the earth’s finite resources is detrimental to overall quality of health (Griffiths, 2006). Quality health can be sustained only in the context of a sustainable society, in which human health is promoted through safe, clean, pleasant environments, and ready access to food, water, housing and fuel (Warrington borough council, 2007), which are considered basic tenets of a traditional public health definition of healthy societies. A major goal, then for public health is the reduction of health disparities in regard to these basic resources, and such disparities cannot be addressed in the absence of a commitment to environmental justice.
The concept of environmental justice includes access to a healthy environment, which includes access to water, food, and fuel as well as protection from pollution and environmental toxins. As such, environmental justice is inseparable from public health. Therefore, education on sustainability must be mainstreamed into our health-related curricula at all levels; not merely “added on.” As educators, it is our responsibility to help our students understand these connections. If not, they will lack the tools necessary to address the major health issues of the 21st century, many of which are likely occur in the context – and as the result of – global climate change, population growth, food, water, and fuel shortages. If the next generation of health professionals does not fully understand these connections they will be ill equipped to prevent or respond to these challenges.
Examples of these challenges include the global burden of HIV/AIDS, the role of climate change in emerging disease, and the growing crisis of environmental refugees. Currently, HIV/AIDS affects an estimated 33 million people. Most HIV infections are in developing countries, with over 67% of the infections occurring in sub-Saharan Africa. In spite of progress that has been made over the past several years in delivering anti-retroviral (ARV) medications to these populations, HIV infections continue to rise, with an estimated 2.7 million new infections and 2 million deaths last year (UNAIDS, 2009).
An example of the connection between the environment and health is the role of water in prevention and treatment of HIV. Indeed, if we had a single dollar to spend on HIV prevention, the best place to spend that dollar would be on access to clean water. In the words of Kofi Annan, “we shall not finally defeat AIDS, tuberculosis, malaria, or any other infectious diseases that plague the developing world until we have won the battle for safe drinking water, sanitation, and basic health needs.” (Global Health Council, 2001).
How is access to safe water, a goal of sustainable societies, linked to HIV? The most obvious link is between unsanitary water and the opportunistic infections associated with AIDS. It is well documented that diarrhea, skin diseases, and other infections negatively impact the life of people living with HIV and can speed the progression of HIV to AIDS (Bery and Rosenbaum, 2009). In addition, even if ARVs are available, diarrheal diseases caused by unsanitary water impede the absorption of the medications, limiting their effectiveness (Bushen, 2004). Hence, it is futile to supply ARVs to people without also addressing the requirements for clean water in order to gain maximum benefits from the drugs.
Access to clean water not only impacts the progression of HIV in infected people; it plays an important role in prevention and transmission of infection. In many developing countries, limited access to water means that people, mostly women and children, must travel great distances to fetch water. Girls often spend up to three hours every day fetching water (Bery and Rosenbaum, 2009). Male water vendors often dominate the water source, making women wait in long lines. As water sources become contaminated or dry up, women and girls may engage in transactional sex with water dealers to obtain water. In addition, women travel great distances to water sources can be raped during their treks to water. In these ways and more, water scarcity drives the transmission of the disease (Siplon, 2008; Fay, 2010).
Closely associated with clean water is the anticipated impact of global climate change on health. As climate changes, many areas of the world will experience increased periods of drought. Local water supplies will dry up or become contaminated, exacerbating the water access issues described. In addition, climate change is likely to lead to increases in morbidity and mortality due to periods of extreme heat or cold (Patz et al., 2005). For example, during the summer of 2003, 22,000 to 45,000 deaths in Europe were attributed to extreme heat. That summer was the hottest on record for Europe in 500 years (Kosatsky, 2005). Climate change may alter the ecology of infectious diseases, most likely via expansion of disease vectors such as mosquitoes and ticks, and changes in waterborne diseases. In some places, changes in weather patterns are likely to lead to increases in heavy rainfall events and flooding. Such events have been associated with increases in waterborne diseases such as cryptosporidiosis, campylobacteriosis, and giardiasis (Hunter, 2003). The anticipated effects of temperature change on vector-borne diseases include: increased survival of vectors, change in vector population growth, changes in incubation periods of pathogens, changes in seasonality of vector activity, and changes in seasonality of transmission (Gubler et al., 2001). One example is Aedes aegypti, the mosquito that carries one of the most prevalent mosquito-borne diseases, dengue fever. This mosquito breeds readily in small water containers. When water supplies are in short supply, people often store water in and around their homes. Studies have correlated the use of such containers during drought conditions with increased populations of Aedes aegypti, thereby optimizing the conditions for dengue fever outbreaks (Hopp and Foley, 2003). We don’t need to look to the future for health effects of climate change. Ten years ago climate change already was estimated to have caused 2.4% of diarrhea and 6% of the malaria worldwide (WHO, 2000).
More and more environments are becoming unlivable due to drought, soil erosion, expanding populations, or over-development. People who are unable to make a living from their land often join the expanding ranks of environmental refugees, migrating to overcrowded urban areas or refugee camps where disease and hunger are a constant presence. The number of environmental refugees is difficult to determine. One estimate puts the number at 25 million people worldwide, with a potential eventual increase to 200 million within the next 40 years (Myers, 1997). The current global health infrastructure is not equipped to handle this wave of refugees from environmental degradation.
Many of the described sustainability challenges are greatest in developing countries. Why, then, should students who plan to practice health care in the United States be educated in environmental sustainability? Aside from issues of social justice and altruism, why is such an education required? While perhaps not as inherently obvious, many diseases in the developed world have environmental links. The WHO estimates that 13% of the disease burden in the U.S. – including diseases such as cancer, respiratory infections, neuropsychiatric disorders, cardiopulmonary disease, asthma, and lead poisoning – is associated with environmental causes (WHO, 2009). As we confront dramatic changes to our fiscally unsustainable health care system in the United States, an often-missing component of this debate is the price we pay for living in environmentally unsustainable communities. In an assessment of health costs associated with morbidity and mortality in children, it has been estimated that environmental pollutants are responsible for annual costs of $54.9 billion; 2.8% of total U.S. health care costs (Landrigan et al., 2002). In short, the U.S. could save billions of dollars in health care every year by vigorously addressing environmental concerns.
Students who plan to commit their professional lives to the promotion of health should be encouraged to reflect critically on how their actions impact global health. For example, the use of food-based biofuels is a topic rarely addressed in a health training program curriculum, but one that has serious health implications. In 2005, when oil prices jumped to over 60 dollars a barrel, corn-based ethanol became very profitable, leading to one-fourth of the U.S. corn harvest being used for fuel, and a shortage of corn for food (Brown, 2009). Such shortages impact food prices, leading to decreases in food shipments from agencies such as the Word Food Bank. Such decreases in aid can be catastrophic to the 1.02 billion people who do not have enough food to eat (Dugger, 2007). In 2007, the number of undernourished people increased by 75 million; in 2008 this number increased by another 40 million (World Food Program, 2009). In a world where a child dies every six seconds due to hunger and related diseases (FAO, 2004) all of us, teachers and students alike, should consider that the grain needed to produce ethanol to fill a 25-gallon tank one time will feed a person for a year (Brown, 2007).
In regard to sustainability, what are the roles and responsibilities of the hospitals and clinics that will employ our students? The focus of most hospitals is the treatment of disease through surgical or other interventions, often without much attention to sustainable environmental practices. Ulhoi argues that hospitals, whose mission inherently involves helping people in need of medical assistance and advising people on how to achieve healthy lives, should avoid behaviors that negatively impact human health. As such, hospitals should not participate in environmentally unsustainable activities (Ulhoi and Ulhoi, 2009). In other words, hospitals should embrace even higher expectations related to sustainable activities than do other organizations due to their unique mission to help, treat, and heal humans (Ulhoi and Ulhoi, 2009). Presently, hospitals are staffed with specialists, trained in a reductionist tradition. Such professionals have little experience or training in sustainability. As new health care professionals enter the field, it is imperative that they understand their role in contributing to a sustainable, healthy community.
As educators we have a responsibility to engage all of our students in discussions regarding the complex and interrelated issues of environmental sustainability, social justice, and human health. Sustainability requires contribution from many disciplines. Such interdisciplinary perspective is a hallmark of education in public health. As McMichael asserts, the goal of environmental sustainability is “not just about maintaining the flows from the natural world that sustains the economic engine nor maintaining the iconic species and iconic ecosystems. It is about maintaining the complex systems that support health and life. Population well-being and health, understood thus, become the real bottom line of sustainability” (McMichael, 2006).
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