One health, food security, and veterinary medicine

Alan M. Kelly Center for Animal Health and Productivity, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348.

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James D. Ferguson Center for Animal Health and Productivity, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348.

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David T. Galligan Center for Animal Health and Productivity, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348.

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Mo Salman Animal Population Health Institute, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523.

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Bennie I. Osburn Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616.

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At the Group of Eight (G8) Summit in L'Aquila, Italy, in July 2009, the leaders of the world's largest economies committed to “act with the scale and urgency needed to achieve sustainable global food security.” The statement was precipitated by spikes in food prices, a rising incidence of hunger in 2008, a realization that price spikes are likely to recur, and an understanding that global food security is among the most formidable challenges facing all of humankind in the 21st century. This urgent global challenge will require a dramatic and coordinated effort by multiple stakeholders, including a crucial role for the veterinary profession in the United States and the developing world.

The world's livestock sector is growing at an unprecedented rate, driven principally by urbanization and rising incomes. Because of this, annual meat production is projected to increase from 218 million tonnes from 1997 through 1999 to 376 million tonnes by 2030, an increase of more than 70% in 30 years.1 To meet the demand, global livestock and poultry production must increase in efficiency. Animal-source foods are important for nutrition of young children and pregnant and lactating women because of the high-quality protein and bioavailable micronutrients they contain. Even small quantities of meat, milk, or eggs can make substantial differences to the food security and health of people living in poor communities.2 The livestock sector can also be an important way of lifting small farmers out of poverty. These factors present the veterinary profession with an opportunity to become a pivotal force in overcoming many aspects of food insecurity by improving the health and economic prospects of millions of small livestock farmers, especially in the developing world, where private and public veterinary services for livestock and poultry production, disease control, animal welfare, and environmental sustainability need to be strengthened. Such long-term, complex challenges require veterinary expertise at multiple levels, especially at the level of formulating and implementing policy. Presently, however, there is an exteme paucity of veterinarians involved in strategic planning in US agencies for international development. We are aware of only a single veterinarian working at the US Agency for International Development (USAID), and this may not be a permanent position. The World Bank, with 9,000 employees working in 124 countries of the developing world, has only 5 veterinarians on staff. Although some of these appointments may be strategic, to our knowledge, none of the veterinarians were educated in the United States. The Food and Agriculture Organization of the United Nations (FAO) has a professional staff of 1,847 that includes 27 veterinarians, but it appears that only one is a US veterinary college graduate.

Although the location of one's veterinary education does not necessarily reflect subsequent job performance, these figures raise at least two questions. Does veterinary education in the United States adequately prepare students for careers in food security and global policy development? And, with rapidly increasing global livestock industries, why there are so few veterinarians in staff positions at these agencies and does the paucity involve other aspects of the livestock sector? When an infectious disease emergency occurs, veterinary positions emerge at these agencies, but they disappear when the crisis is over. Nonetheless, animal health and productivity, food safety, food security, and the growing crisis of hunger in the world are continuing challenges that directly involve the veterinary profession. For example, we are surprised that in the midst of a livestock revolution, the USAID has embarked on Feed the Future,3 a US government–sponsored $3.5 billion global hunger and food security initiative, without a single veterinarian in a permanent staff position. Policies on production efficiencies and social constraints; the impact of urbanization, infrastructure, and access to food that is perishable; environmental and food safety regulations; how endemic diseases should be controlled; water conflicts; and research support are among the many issues that are crucial to the goals of food security where the special knowledge of veterinarians is important and can provide leadership.

Veterinary medicine had its origins in food production and has had important roles in dealing with the devastating effects of infectious animal diseases on livestock industries as well as in mitigating human diseases of animal origin. This historical legacy is the foundation of an essential veterinary medical domain. Nonetheless, infectious disease control alone is unlikely to automatically lift small farmers out of poverty. Animal nutrition, animal welfare, market access, and the infrastructure necessary to bring perishable products to consumers are as important as disease control and involve veterinarians as an integral part of a food system. And because global animal production systems are so diverse, food animal veterinarians must understand and work comfortably within the framework of local social, cultural, and political conditions and constraints. We believe that veterinary schools and colleges, working with the One Health Consortium, should consider all these issues and develop a vision for veterinary education that sees livestock disease control and productivity as a continuum, going beyond disease control to include production efficiencies, economically based agricultural development, the potential impact on the food system of changes in technology, ecosystem health, urbanization, public health, and the multidisciplinary collaborations necessary to generate sustainable food policies.

Agriculture has to be at the core of solutions to food insecurity and relief from hunger and malnutrition. Available arable land and water supplies are finite, indicating that agriculture must intensify and produce far more from much less. Also, agriculture must shift its emphasis to methods that focus on increasing urban markets, access to food, and environmental sustainability. For these issues to be addressed successfully, governments of countries in the developing world should be committed to agricultural development and, where appropriate, receive assistance from the developed world.

Feed the Future,3 the $3.5 billion program of the USAID that was introduced by President Obama at the L'Aquila Summit, and Realizing a New Vision for Agriculture,3 introduced at the World Economic Forum in 2011 by the B20 (a consortium of almost all the world's major food companies)4 with an initial pledge of up $15 billion, are among the programs sponsored by agencies that recognize both the critical needs and the necessity for public and private partnerships in formulating policies to overcome food insecurity. Because 70% of those who are hungry and survive on < $1.25 a day are located in rural areas, solutions will require research focussed on improving rural economies. In addition to improving the efficiency of food production, investment is needed in food supply systems, infrastructure development, hygienic and humane slaughter plants, temperature-controlled supply chain facilities to reduce spoilage and waste, and access to markets in distant cities.

The challenge is daunting. In the next 40 years, if agriculture is to feed a world population that is projected to increase by 30% to 9 billion people by the year 2050, it must produce more food than it has in all of the past 500 years.5 This equates to feeding more than 1 million additional people every week for the next 40 years. However, the problem of food insecurity is not just about the increasing number of people who must be fed; dietary transitions and greatly increased demand for meat and milk among urban communities substantially increase the task and magnify the challenges for veterinary services. Needs must be met with scarcer resources while dealing with the effects of climate change, water shortages, soil degradation, and global price volatility. Moreover, food must be produced in a sustainable manner so that what is purchased today does not come at an environmental cost for those yet to be born.

Approximately 1 billion people in the world currently suffer from chronic hunger because of extreme poverty, and up to 2 billion exist on < $2 a day and intermittently lack food security.6 Seventeen thousand children in rural and urban areas die of hunger every day, and many more are physically and cognitively stunted as a result of malnutrition7 and are unlikely to climb out of poverty as a result. Presently, most of the world's poor people live in rural, usually marginal areas and depend on agricultural work for survival. For them, livestock are important—two-thirds depend on livestock to provide up to half their household income.8,9 They see local economic growth as the most important solution for relief of poverty and hunger. The poor invest a high proportion of their resources on food and are particularly vulnerable to fluctuations in food prices. Furthermore, they have difficulty affording food that is safe. Consequently, as prices rise, not only does the incidence of hunger and malnutrition increase, so too does the incidence of food-borne disease.

One way of looking at the complexity of the present day food insecurity problem is to follow the achievements and failures of the Green Revolution. The term describes the large increases in wheat and rice yields in countries of South Asia that followed the introduction of new high-yielding strains of rice and wheat, combined with the use of irrigation, fertilizers, and agricultural chemicals. Starting in the 1960s, these initiatives produced more than a 250% increase in cereal yields from existing cropping areas in South Asia. As a result, global food supplies became relatively abundant and for the ensuing years, up until 2004, food prices remained low and food riots were uncommon. The Green Revolution is credited with saving over a billion people from death by starvation. In addition, the increased yields of the Green Revolution decreased deforestation and spared wildlife habitat, showing that, when responsibly managed, high-yield farming can be a way of saving human lives while allowing wild species to survive.10 In India, for example, the Green Revolution's high-yield farming methods are estimated to have saved 100 million acres of virgin land, an area about the size of California, from being converted into farmland.

The Green Revolution remains important, but in recent years, its impact has diminished owing to rising fuel and fertilizer prices and both inefficient methods and dwindling water resources for irrigation. With this decline, an era of cheap food came to an end; prices started to rise in 1994, and food insecurity became a growing concern.11 In the face of global warming, we require a new, highly efficient sustainability revolution. However, such an initiative will require the realignment of priorities and greatly increased funding in agricultural research, including in the United States, where investment has steadily decreased for more than 40 years.12 The FAO estimates that global agricultural investments should increase by at least 50% by 2050 if there is to be enough food for 9.2 billion people.

One important approach to meeting the increasing demand and to decrease the pressure for more food production is to diminish food losses. It has been estimated that a third of total food production in the world is lost or wasted during the processing, marketing, and consumption steps.

The Green Revolution stimulated remarkably rapid economic growth and urbanization in South Asia. Throughout history, very few countries have experienced rapid economic growth without a preceding or concomitant growth in agriculture; technical advances in agriculture have consistently been the engine of growth, and the Green Revolution is no exception. The United Nations Population Office projects that by 2050, two-thirds of the population of Asia, the world's largest and most populous continent, will live in cities.13 Because of income growth created by the cities, the World Bank estimates that by 2030, there will be 1.2 billion middle-class people in the developing world, a 200% rise from 2005 and a number that is greater than the current populations of the United States, Europe, and Japan combined.14 This growing and more comfortable class is demanding a better diet, one that includes fruits, vegetables, eggs, meat, and milk. As a result, the emerging middle class is reshaping agriculture, pushing it toward intensive systems of production and driving the Livestock Revolution described by Delgado.15

The quantities of food that cities need are staggering; for example, a city of 4 million people is estimated to need 3,000 tons of food delivered every day to be sustained.16 This places enormous pressure not only on food production, but equally on transportation and food distribution systems, which are already deficient in many cities of the developing world. Urban and periurban farming, including livestock and poultry production, need to be considered from this perspective. In hungry cities, access to food is critical to food security, and until the food supply infrastructure is improved, periurban farming will remain important.

The World Bank projections for the unprecedented rise of the developing world's middle class emphasize that food security is increasingly an urban problem. The locus of global poverty is also progressively shifting to cities, where the divide between socioeconomic classes is growing and the number of people living in urban slums is on the rise. The United Nations Human Settlements Programme projects that in the next 30 years, the number of people living in slums could rise to 2 billion, 22% of the world's population.17 Fifty-one percent of Africa's urban population already live in slums.16 Reasons for this increase differ by region. In South Asia, people are pulled to cities with the prospect of better jobs, whereas in sub-Saharan Africa they are pushed to cities because of conflict, deterioration of rural life, and failures of agriculture. The characteristics of food insecurity also differ. The poor in rural areas may produce up to 60% of their own food and barter for the rest.18 For them, food insecurity primarily follows disease or environmental calamity. In cities, the poor may be equally susceptible to environmental calamities but must pay for food with cash. They must have income to survive and are especially vulnerable to food price spikes. Urban populations also need access to food that is affordable, safe, and nutritious. Food riots and conflicts ensue when these staples are not available, emphasizing the central link that exists between food and national security.

In view of these demographic shifts, the veterinary profession must consider food insecurity on two fronts, one urban and the other rural, with each requiring different approaches and different forms of assistance. To meet growing urban demand, livestock farming in China and South Asia is progressively shifting to intensive methods of production, including confined animal feeding operations. Since 1990, 80% of the increase in total livestock production in the developing world has come from these sources.19 Locating in periurban areas is common largely as a result of weak food distribution infrastructures. This is likely to continue because confined animal feeding operations are an expedient way of catering to burgeoning urban demand. As they benefit from economies of scale, livestock operations have become larger and progressively more intensive. They have also become more and more efficient owing to the application of technical advances that enable them to dependably supply pork or poultry products that are lower priced and more consistent in quality and safety than products from most other sources. However, the disadvantages are considerable. Locating large numbers of livestock and poultry close to heavily populated areas raises public health concerns about the risks of zoonotic disease transmission. Efficient systems for waste disposal are lacking, resulting in major problems with pollution of streams and rivers, while animal welfare issues are a growing public concern for these and all of livestock and poultry farming.

Despite their shortcomings, intensive systems of production and confined animal feeding operations are likely to persist and challenge the veterinary profession to institute policies that safely, responsibly, and humanely address the challenges. In the United States, farmers involved in intensive systems of livestock and poultry production seek food animal veterinarians who understand production systems and can read farm records and use them to make decisions aimed at increasing herd health and welfare, productivity, safety, sustainability, and overall profitability of the farming operation. American farmers seek production medicine's objective services, and we anticipate that producers in the developing world are no different.

All of these seismic transitions have occurred with remarkable speed and are dependent on competent management. Veterinary services in Southeast Asia are thus under great pressure to adjust their practices to meet the new challenges that have resulted from rapid urban growth, booming economies, and swift consolidation of livestock and poultry industries. As a result, they frequently lack the capacity to respond. The Director General of the World Organization of Animal Health (OIE) has noted the inadequacy of veterinary education in most OIE member countries and has emphasized the importance of improving the quality of veterinary education in these parts of the world. In view of this, the veterinary profession in the United States has a unique opportunity to help the transition of veterinary services by providing collaboration and direction on standards of humane animal care, responsible environmental stewardship, and the concepts of production medicine.

A further impact of the Green Revolution has been to increase the prosperity of large farms and marginalize small farmers. With small plots of land, small farmers are unable to risk new technologies and do not have the resources or access to credit to purchase new seed, fertilizers, and pesticides. The Livestock Revolution, inadequate transportation infrastructures, and growth of urban supermarkets have further marginalized small farmers. In the interests of food security, however, and because there are millions of small farmers in the world, they cannot be forgotten. Moreover, at least 70% of the roughly 1 billion people who survive on < $1.25 a day live in rural areas, keep livestock or poultry, and descend further into desperate need when these animals are lost. The HIV/AIDS epidemic is among the most important reasons for this to overtake a family.

Few small livestock farmers in the developing world receive veterinary care. A recent landmark study9 mapping poverty and likely zoonotic hotspots illustrates the strong correlation between poverty, livestock keeping, and endemic zoonoses. The study9 found that endemic zoonoses affect many people and animals and are responsible for most human cases of infectious illness. Together, 56 zoonotic diseases are assessed to be responsible for approximately 2.5 billion cases of human illness and 2.7 million human deaths each year as well as reductions in livestock production. It is hard to imagine a more compelling argument in support of one health.

Thirteen zoonoses, including gastrointestinal tract disease, leptospirosis, cysticercosis, zoonotic tuberculosis, rabies, leishmaniasis, and brucellosis, were identified as the most important to poor livestock keepers because of their impacts on human and livestock health, their amenability to agriculture-based control, and other criteria. The authors of that report5 note that endemic zoonoses are of most concern in those areas where the objective is to lower the burden of human disease while increasing the productivity and profitability of livestock for the poorest people.

Sustainability of livestock operations among small farmers is also important. Presently, the increasing demand for animal protein in Central America, Latin America, Africa, and much of Asia is being met by augmenting the numbers of animals, with little regard for increasing their productivity. This is the case for countries in the Sahel, which has suffered through a series of droughts in recent years. According to the FAO, between 1961 and 2007, Burkina Faso, Cameroon, Ghana, Mali, and Tanzania enlarged their cattle populations between 220% and 450%, with negligible changes in carcass yields.a Although livestock ownership denotes wealth in these cultures, the present course is not only inefficient, it is environmentally unsustainable. Overgrazing, deforestation, and poor management in combination with large-scale climate change contribute to desertification and drought, underscoring the need to educate producers and improve methods of livestock production through breeding, genetics, nutrition, management, and veterinary interventions.

To build a rural economy in the developing world, ensure the success of livestock operations, and persuade young people to stay will require not only raising animal productivity, but also offering a vision of continued growth. Competent, reliable, and efficient veterinary medical services are important for this to come about. However, the magnitude of the challenge is daunting because, for the past several decades, there has been an abysmal lack of investment in veterinary medicine as well as in agriculture in the developing world.20,21 As a result, the veterinary profession in many of these countries is underfunded, is not highly regarded, and does not have the capacity to meet rapidly growing and changing demands.20,21 Recognizing this, the veterinary profession in the United States and the one health initiative are presented with an opportunity to lay out a roadmap for building capacity and empowering the developing world's veterinary profession to assume its uniquely appropriate role in providing safe, affordable, humanely produced, and environmentally responsible foods of animal origin. The OIE has recently published a useful set of recommendations advocating this course. Without such intervention, the goals of sustainable food security are unlikely to be realized, rising demand for animal protein will remain unmet, and millions of rural poor who depend on livestock for survival will face a difficult future.21

A health-care network of veterinarians, paraprofessionals, community animal health workers, and other agricultural specialists is needed to provide affordable and reliable disease surveillance, primary care, access to diagnostic services, and consultation on herd health management, productivity, and economic success covering vast land areas of the developing world. Because services that are paid for are generally valued more than those that are provided free, we believe that livestock health care should, to the extent possible, be offered privately. However, working in the private sector is not the norm for veterinary medicine in many parts of the developing world, and there are opportunities for veterinarians from the developed world with training in global food security and production medicine to serve as consultants working with nongovernmental organizations and new democratic governments to expedite the transition.

Ten years ago, this might have seemed like an impossible task, but the advancement of digital technologies and proliferation of mobile phones in the developing world potentially redefine the problem. They offer the veterinary profession in the United States and Canada the opportunity to help build veterinary capacity in animal health in developing countries, create integrated virtual extension systems, and advance sustainable methods of livestock and poultry production. In view of this, we see the veterinary medical profession in the United States and specifically the one health initiative as central to the immense, multidisciplinary challenges of food security. We suggest that the many advocates of one health and veterinary academia in the United States should play a pivotal role in strengthening the quality, research potential, and status of veterinary institutions in the developing world and find financial support from public and private agencies to do so. For this, the veterinary profession's engagement in food policy development is critical. We suggest the new landscape requires not only an understanding of infectious disease control and food safety, but also a holistic understanding of the skills needed by increasingly intensive, specialized, and concentrated livestock and poultry industries both in the developed and developing worlds.

The developing world is changing rapidly, and the challenges of hunger and food security are not only increasing, but also becoming far more complex. In collaboration with specialists from other disciplines, the veterinary profession has an opportunity to help poor countries sustainably meet their demand for foods of animal origin. However, too few people are aware of all that veterinary medicine has to offer, and as a result, the profession does not receive adequate support. Academic veterinary medicine needs to step up efforts to better prepare future graduates to address not only improved animal and human health as captured under the banner of one health, but also the broad issues of poverty, hunger, sustainability, food systems, and food security. To accomplish these more expansive goals will require schools of veterinary medicine and schools of agriculture to work together to create solutions. New veterinary graduates should be made aware of the unique role veterinary medicine has to play in achieving food security in the developing world and be encouraged to pursue careers in strategic planning with international development agencies. We fear that failure to address these issues collectively will result in an ever declining role for veterinary medicine in global society. High-level positions in multinational food corporations and governing bodies such as national and international agencies, nongovernmental organizations, and foundations are essential if the veterinary profession is to evolve as a productive partner in addressing the urgent issues of global hunger, poverty, and food insecurity.

a.

FAOSTAT [database online]. Rome, Italy: Food and Agricultural Organization of the United Nations, 2010. Available at: faostat.fao.org/. Accessed Dec 8, 2012.

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