Summary

Epidemics of infectious diseases have been among the most frightening and disruptive of natural disasters at least since the Middle Ages, when recurring outbreaks of the plague killed millions of people. Today, conditions around the globe are ripe for the development of epidemics of zoonotic diseases (any disease or infection that is naturally transmissible from vertebrate animals to humans1) that have the potential to become pandemics. Many of these diseases, among them AIDS, Severe Acute Respiratory Syndrome, highly pathogenic avian influenza (HPAI-H5N1) and Bovine Spongiform Encephalopathy causing variant Creutzfeldt-Jakob disease in humans, have emerged recently as the patterns of human–animal contact have changed. What accounts for this upsurge in the incidence of this type of infectious diseases? Some of the answers from the June 2008 workshop convened by the Institute of Medicine and the National Research Council’s Committee on Achieving Sustainable Global Capacity for Surveillance and Response to Emerging Diseases of Zoonotic Origin are outlined in Chapter 2 of this summary.2

1

The World Health Organization state in their definition of zoonoses: “Animals thus play an essential role in maintaining zoonotic infections in nature. Zoonoses may be bacterial, viral, or parasitic, or may involve unconventional agents. As well as being a public health problem, many of the major zoonotic diseases prevent the efficient production of food of animal origin and create obstacles to international trade in animal products” (WHO, 2008c).

2

This document summarizes the views expressed by workshop participants. While the committee is responsible for the overall quality and accuracy of the document as a record of what transpired at the workshop, the views contained in the document are not necessarily those of the committee. Copies of the workshop presentations can be accessed at www.iom.edu/zoonotics.



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Summary E pidemics of infectious diseases have been among the most fright- ening and disruptive of natural disasters at least since the Middle Ages, when recurring outbreaks of the plague killed millions of people. Today, conditions around the globe are ripe for the development of epidemics of zoonotic diseases (any disease or infection that is naturally transmissible from vertebrate animals to humans1) that have the poten- tial to become pandemics. Many of these diseases, among them AIDS, Severe Acute Respiratory Syndrome, highly pathogenic avian influenza (HPAI-H5N1) and Bovine Spongiform Encephalopathy causing variant Creutzfeldt-Jakob disease in humans, have emerged recently as the patterns of human–animal contact have changed. What accounts for this upsurge in the incidence of this type of infectious diseases? Some of the answers from the June 2008 workshop convened by the Institute of Medicine and the National Research Council’s Committee on Achieving Sustainable Global Capacity for Surveillance and Response to Emerging Diseases of Zoonotic Origin are outlined in Chapter 2 of this document.2 1 The World Health Organization state in their definition of zoonoses: “Animals thus play an essential role in maintaining zoonotic infections in nature. Zoonoses may be bacterial, viral, or parasitic, or may involve unconventional agents. As well as being a public health problem, many of the major zoonotic diseases prevent the efficient production of food of animal origin and create obstacles to international trade in animal products” (WHO, 2008c). 2This document summarizes the views expressed by workshop participants. While the com- mittee is responsible for the overall quality and accuracy of the document as a record of what transpired at the workshop, the views contained in the document are not necessarily those of the committee. Copies of the workshop presentations can be accessed at www.iom.edu/zoonotics. 

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 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES Changes in the human population and its behaviors, including inten- sifying means of food production and transport systems, more rapid travel and transport of people and animals across borders and continents, and changing patterns of land use have contributed to this upsurge. Other envi- ronmental changes and a host of additional factors have also contributed to conditions that favor the transmission of pathogens that develop in animal populations, then make the jump into human populations. Researchers and human and animal health advocates have focused on disease surveillance3 as a particularly critical tool for detecting, monitoring, and facilitating response to control outbreaks of zoonotic diseases in humans, but questions remain as to how to make zoonotic disease surveillance more comprehen- sive and timely in animal populations in order to prevent or minimize the potential for outbreaks to occur in human populations. THE CONVERGENCE OF FORCES RESPONSIBLE FOR ZOONOSES IN HUMANS These newly identified diseases have emerged4 primarily as a result of significant changes in human activity: population growth, changing patterns of human–animal contact, increased demand for animal protein, increased wealth and mobility, environmental changes, and human encroachment on farm land and previously undisturbed wildlife habitat. Other pathogens could follow a similar pathway. Human factors that influence the development of pathogens include genetic and biological factors; social, political, and economic factors; human health, behavior, and attitudes; and activities such as transport and trade. Perhaps the most obvious change has been the growth in human population. At less than 3.5 billion in 1950, the world’s population reached approximately 6.5 billion in 2005 and is projected to top 11 billion by 2100 (Kern, 2008). The largest proportion of human population growth is 3 The World Health Organization defines surveillance as “the systematic ongoing collection, collation, and analysis of data for public health purposes, and the timely dissemination of public health information for assessment and public health response as necessary”; surveillance may be conducted by institutions of various kinds (WHO, 2008a). 4 For purposes of this workshop summary, a human disease is considered emerging if it meets one or more of these characteristics: has nearly appeared or is newly recognized, is more difficult to treat, has an increased incidence, is widely distributed geographically or demographically, is severe or lethal, presents new complications, has a new mode of trans- mission, has substantial epidemic potential, or threatens regional of global health (Breiman, 2008). The National Institute of Allergy and Infectious Diseases, however, defines emerging and re-emerging diseases as the following: “emerging diseases includes outbreaks of previously known diseases whose incidence in humans has significantly increased in the past two decades. Conversely, remerging diseases are known diseases that have reappeared after a significant decline in incidence” (NIAID, 2008).

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 SUMMARY taking place in the least developed countries, those with the highest rates of poverty—and also those that are least equipped to monitor, detect, and control emerging diseases. Global population expansion has brought signifi- cantly increased challenges in sustaining the food supply and may have con- sequences to human and animal health. For example, an increased demand for protein and food of animal origin has resulted in noteworthy changes in basic animal husbandry practices to more intensive systems due to the increases in the number of animals kept. This in turn has altered disease exposure risks from livestock to humans and from wildlife to livestock. Other changes made possible by technological advances have also affected the development of pathogens. One can now circumnavigate the globe in 24 hours and the fast-growing human population is moving more, and more quickly, than ever before. An estimated 1 billion people cross international borders every year. Humans are also transporting goods, par- ticularly meat and other food, on a vast scale, which means that animals and pathogens can travel farther and faster than ever before. Pathogens are also affected by changes in the environment, most of which are widely viewed as traceable to human activity. Climate and weather have changed in numerous ways around the world.5 Changing temperature and humidity patterns, drought and desertification, novel weather patterns, and other changes have not only affected the geographic ranges in which species can thrive, but have also altered lifecycles and microclimates. These changed patterns are expected to affect the distribution and movements of pathogens and their vectors. Finally, human encroachment on the environment can affect animal health and behavior. The availability of land for both domestic and wild animals has fallen considerably. Animal behavior and feeding preferences may be altered as they adapt to new ranges, and other factors may affect the balance within an ecosystem. Animals may also be exposed to new disease-causing agents as they move or come into contact with humans and other species, and their acquired resistance to new disease may be reduced by fast-paced changes in their environment. These interactions provide ideal circumstances for pathogens that affect only animals to evolve first into agents that can cause primary infection in humans, through direct animal–human contact (e.g., canine-rabies), to those that can cause limited outbreaks through human–human contact, as well as through animal–human contact (e.g., Ebola). The next evolutionary stage is to an agent that can cause a sustained outbreak via animal–human or human–human contact (e.g., Chagus or influenza A). Eventually, given 5 Datafrom the Intergovernmental Panel on Climate Change leave little room for doubt that the world is getting warmer (IPCC, 2007).

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 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES the right circumstances, a pathogen may develop into an agent transmitted only among humans (e.g., HIV). SURVEILLANCE Surveillance, which has been defined by the World Health Organization as “the systematic ongoing collection, collation, and analysis of data for public health purposes and the timely dissemination of public health infor- mation for assessment and public health response as necessary,” is viewed by most experts in public and animal health as a particularly critical tool for protecting humans from zoonotic diseases and animals from epizootic diseases.6 Surveillance is conducted by institutions of various kinds, and no single agency has either the mandate or the capacity to address the entire landscape of zoonotic disease. Looking worldwide, the World Health Orga- nization (WHO), the World Organization for Animal Health (OIE), and the Food and Agriculture Organization of the United Nations (FAO) each play a role, and have been working to better coordinate their activities. Within the United States, the responsibility is spread across many government departments and programs, each with its own focus and interests. It would be inaccurate to describe current surveillance efforts around the world as a system, but they do interact in important ways. Detecting Disease in Animals with Zoonotic Potential A new zoonotic disease in humans could theoretically emerge from any animal population around the world, but some animal populations are more likely than others to serve as a reservoir for disease that could threaten humans. As a result, much of the current disease surveillance apparatus has developed in a somewhat ad hoc way, in response to growing awareness of specific kinds of threats. Several systems and programs have been especially important. The Global Early Warning System (GLEWS) is one of several current efforts to coordinate and build on existing surveillance networks by pool- ing information collected by FAO, OIE, and WHO. GLEWS was devised as a means of improving the tracking of significant diseases among animals in high-risk areas and providing data analysis and early warnings to the international community. GLEWS was also designed to ensure that data are shared among institutions and agencies, rather than duplicated. The program’s primary functions are disease tracking, information sharing, 6 These principles would also pertain to animal health surveillance. Epizootic diseases are epidemics in animal populations.

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 SUMMARY verification of threats, epidemiological analysis, and support for urgent response to assess and control outbreaks. Consistent standards and procedures applied across countries are a critical element of surveillance and response systems. OIE has developed standards that merge concerns about animal health and welfare, food safety, and public health; they include codes for both terrestrial and aquatic animal health. OIE has 172 member countries, and its objective is to engage each of them in a commitment to conduct surveillance, collect data, and rapidly disseminate data on both the presence of diseases being targeted and other epidemiological events. Although the 172 member countries are legally obliged to adhere to the organization’s notification obligations and published standards, OIE provides a variety of resources to assist them. A decision tree is used to determine which diseases are of concern and should be tracked. OIE has developed a web-based system, the World Animal Health Information System, for managing the data collected and providing additional data resources. While OIE focuses primarily on animals that are domesticated for food consumption, the U.S. Geological Survey conducts surveillance of wildlife and investigates disease outbreaks in U.S. wildlife populations. The health of wild animals is directly linked to that of both domestic animals and humans. Diseases among wild animals can also provide early warnings of environmental damage, bioterrorism, and other risks to human health. Subsistence economies are particularly vulnerable to disease outbreaks among wild animals because they are directly dependent on them for sur- vival, yet these societies are least likely to have adequate (or any) infrastruc- ture and expertise for animal disease surveillance. Often, outbreaks among wild animals are not investigated until implications for human health are evident, but once these connections are clear, it may be too late to contain the disease. Wildlife diseases may have profound effects on an ecosystem, or be evidence of threats to an ecosystem. Moreover, once a wild popula- tion has been depleted or eliminated, there is no mechanism for its replace- ment, as there would be for a domestic population (e.g., Ebola is killing large numbers of great apes in equatorial Africa, while poultry stock has been replaced after culling for highly pathogenic avian influenza in regions of Asia). Wildlife populations can serve as reservoirs and hosts to diseases that also affect domestic animals; though they can then be a vital link in a cycle that could also include humans, they are frequently left out of the surveillance picture. Current wildlife disease data are available from a number of sources, including international programs (e.g., FAO, OIE, Global Avian Influ- enza Network for Surveillance), which encompass only limited voluntary reporting, and U.S. sources (federal-, state-, university-based), which are not coordinated nationally. Most local data are not being shared or used.

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 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES Many workshop participants stressed that relevant health data regarding humans, domestic animals, and wildlife should ideally be coordinated to protect human health. Targeted surveillance systems have developed in response to several specific threats or animal populations as well, one of which is Ebola, a disease that causes hemorrhagic bleeding in nonhuman primates. Ebola has affected fewer than 1,000 humans thus far, but its high fatality rate and the threat it poses to endangered primate species have made the possibility of large-scale outbreaks a particularly chilling prospect. Surveillance of primates is important for several reasons. Populations of many primates are highly concentrated: roughly 80 percent of the world’s gorillas and chimpanzees, for example, are located in Gabon and the Republic of Congo. These and other primates have been under tremendous pressure as a result of commercial hunting and many are now endangered. The ape population in Gabon has declined by more than half since 1983, and although counting these animals has been difficult, as many as 5,500 gorillas are estimated to have died from Ebola. Researchers have been eager to understand exactly how Ebola spreads among these primates, and also whether interaction among different species of nonhuman primates—and possibly with other species, such as bats—may play a role. Investigators have concluded that the incidence of Ebola is most likely caused by a combination of multiple separate emergences and group- to-group spread of the disease, but they have not been able to identify the reservoir for the disease. In any case, primates serve as important sentinels, even though the risk of the disease spreading to other countries is small. Bats are also carriers for viruses that are harmful to humans—perhaps including Ebola. Eight new zoonotic viruses that originated in bats have emerged since 1994, and there is significant potential for additional ones to emerge. Bats are an important sentinel species, in part because bats are the most diverse of all mammals (there are more than 1,000 species), comprise one-fifth of all mammal species, and can be found worldwide. They are also highly mobile and well adapted to human environments, which means they often share food sources and dwellings with people—and human–bat interaction is increasing as humans encroach on tropical forestland. Surveillance of bats is challenging—it entails collection of blood and other body fluids, which can be highly infectious, and must often be carried out in difficult, remote terrain. Bats are very sensitive to disturbance, and colonies may move in response to investigation. Because testing every bat species would be impossible, the strategy must be to focus on so-called hot- spots where zoonoses are most likely to be found—meaning geographical areas with high biodiversity as well as high human population density. Surveillance of any wildlife populations is important not only as an early warning system for diseases in humans, but also as part of an overall

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 SUMMARY approach to sustaining the integrity of ecosystems worldwide. The Wildlife Conservation Society’s (WCS’s) goal is to protect wildlife and wild lands, and they conduct animal disease surveillance both in the wild and in controlled settings. One of their surveillance activities has focused on bushmeat (ter- restrial wild animals hunted for food), as (1) the demand for wildlife food has increased significantly in many remote areas and (2) increased trade in wild animals, both legal and illegal, has meant increased interactions between humans and wild animals, and increased opportunities for disease. Many of the diseases that humans contract from interacting with wild- life are easily preventable by following certain hygienic steps, particularly during animal handling and food preparation, but these disease prevention practices are not well understood by those who rely most on bushmeat for survival. For that reason, educating and training local populations are a priority for disease prevention and control. At the same time, populations that have daily contact with wild animals are in a good position to contrib- ute to both surveillance and protection. The WCS also encourages countries and local authorities to see the importance of surveillance and to build their own capacity to collect and analyze samples. The challenge of wild animal surveillance is identifying viruses with epidemic potential before they emerge or spread extensively. Yet, there are approximately 50,000 vertebrate species that each might normally carry 20 unique unknown viruses—translating into a global biodiversity of a million unknown vertebrate viruses, many of which are likely to be zoonotic. Companion animals are also excellent sentinels for emerging infections that can affect humans, in part because they are much easier to monitor than wild animals. At least 170 million dogs and cats are kept as compan- ion animals in United States, generally in close contact with their owners; companion animal ownership is growing in many developing countries as well. These animals are reservoirs for many diseases, such as leptospirosis, that affect humans, and they may be more sensitive to a fixed pathogen dose. They are also highly susceptible to threats such as bioterrorism and emerging diseases. Purdue University and Banfield® Pet Hospitals have collaborated to sponsor the National Companion Animal Surveillance Pro- gram (NCASP), which provides a range of health data with epidemiological significance. NCASP maintains a database that enables it to respond quickly to an event by tracking illness outbreaks against baseline data. The data from Banfield® Pet Hospitals provide access to standardized, computerized medi- cal records from more than 3.5 million annual veterinary patient visits in 49 states and from all major U.S. population centers. With each animal’s unique identifier number, investigators can track disease events by neigh- borhood, track laboratory results and other health information, and obtain biological specimens when necessary. The kinds of data collected include

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 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES records of companion animal demographics, exam observations, laboratory findings, medical notes, ailments diagnosed, and treatments. These data can be integrated with data from other local, state, and national surveillance systems. However, participants noted a long-term investment will be needed to fully integrate animal data sources in the United States alone (including private- and state-run veterinary practices, diagnostic laboratories, and surveys). A further goal would be to integrate veterinary data with human health data, and with international data. Diseases in Humans—Early Warning Systems Like surveillance of animals, surveillance of zoonotic diseases that are affecting humans is focused on early warning. There are numerous pro- grams and organizations contributing to this effort as well. One example is the Global Public Health Intelligence Network (GPHIN), originally devel- oped by the Public Health Agency of Canada in collaboration with WHO. GPHIN is an automated, web-based data mining system to track and filter news reports of outbreaks from around the world. Subscribers include governments as well as nongovernmental organizations and agencies. The GPHIN network monitors news sources in at least seven languages around the world, and monitoring continues 24 hours a day, 7 days a week. Sources include websites, news wires, and other Internet-based information outlets. GPHIN tracks not only outbreaks of disease, but also contamination of food and water; natural disasters; and chemical or biological exposures caused by terrorism or accidents. Once the surveillance provided by GPHIN has identified an outbreak, the Global Outbreak Alert and Response Network (GOARN) is activated. Also developed under the auspices of WHO, GOARN is a network of 200 partners, institutions, and organizations worldwide that provide coordi- nation, expertise, and technical support to detect and respond to disease outbreaks. GOARN provides technical support to affected populations, investigates and characterizes disease events, and provides other support to resource-challenged nations. Another system that tracks disease outbreak information around the world is ProMED-mail, a project of the International Society for Infectious Diseases that provides means of quickly disseminating infectious disease outbreak information. It has more than 40,000 subscribers in 160 countries who are the source of much of the data handled by the system. Volunteer rapporteurs and moderators with expertise in 22 areas search the Internet for information about emerging diseases, including official sources, then verify and disseminate it for volunteer subject-matter expert analysis to determine the need for further action within their system, including a post- ing to their subscribers.

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 SUMMARY Another disease surveillance system has been developed by the U.S. Department of Defense (DoD) to monitor and respond to infectious dis- eases that are a threat to military personnel or their families, reduce medi- cal readiness, or present a risk to national security. The Global Emerging Infections Surveillance and Response System (GEIS) was established by a Presidential directive in 1996, in response to growing recognition of the potential threat infectious diseases pose to the military. DoD-GEIS focuses on respiratory illnesses, febrile illnesses, enteric disease, antimicrobial resis- tance, and sexually transmitted infections, but it also has a pilot program attempting to integrate both human and animal disease surveillance and information sharing. ArboNET, a U.S. national surveillance system for arboviral diseases (those transmitted by hemophagic arthropods, e.g., mosquitoes and ticks) maintained by the Centers for Disease Control and Prevention (CDC) was developed in 1999 in response to the emergence of West Nile virus in the United States, and was expanded to cover other arboviral diseases in 2003. ArboNET is a comprehensive system that collects six types of data. Sources include health care providers, veterinarians, and commercial laboratories, who report information to a state or local health department. With these data it is possible to broadly see where disease reservoirs, transmission, and vectors are occurring and migrating. Collaborations among CDC, state and local health departments, and blood services agencies, as well as rapid turnaround, allow for quick response. However, ArboNET provides only minimal clinical and laboratory data, and cannot confirm that patients meet case definitions. Moreover, potentially long delays between the time that cases occur and the time they are reported are beyond the network’s control. Some of the data are not reportable by law, and the variable results may not be representative. Finally, this system works differently than those used for other notifiable diseases, which limits the potential for coordination. The Emerging Infections Network (EIN), another project of the Infec- tious Diseases Society of America, is a network of infectious disease spe- cialists who contribute clinical data to assist CDC in identifying emerging diseases. It began with the goal of establishing a permanent system to allow rapid communication about symptoms that clinicians see, how they are responding, and so forth—both among clinicians and with CDC. The goal was not to replicate systems already in place, but to fill gaps. EIN now has approximately 1,200 members who are pediatricians or internists through- out the country, as well as approximately 130 public health officials.

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0 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES CAPACITY The participants’ examination of current surveillance systems made it clear that capacity is a primary issue in many parts of the world, and their look at several existing structures illustrates the need. For example, laboratory standards have been established to protect humans, animals, and the environment. Both WHO and the U.S. govern- ment have published standards for humans and the environment, while OIE has developed standards for protecting animals and the environment. Among the key elements spelled out in laboratory standards are four con- tainment or biosafety levels (BSL-1 through BSL-4) for handling patho- gens. Many of the procedures for higher levels of biosafety are difficult for resource-constrained countries to establish or maintain. Specifically, BSL-2 laboratories are available and widely used, but few, if any, laboratories meet all the requirements for BSL-3 in resource-constrained countries. This means that many countries lack the capacity for virus isolation for influ- enza while BSL-4 laboratories are available in only a few of the wealthiest nations. High equipment costs are a principal impediment to setting up a laboratory that meets higher levels of containment. Data from a 2007 FAO survey of 20 Western and Central African coun- tries showed that most of them have adequate laboratory infrastructures and staff who have received basic training, though the quality of the facilities and the diagnostic performance are highly variable. Equipment is available, though in some cases no personnel are available to maintain it. On the other hand, two of the countries surveyed have no facilities, and an additional three have facilities that were not functioning at the time of the survey. Many laboratories need renovations or upgrades, and many staff need customized training on specific issues. Laboratories surveyed also lack reagents because of cost, lack of local suppliers, or rapid deterioration in extreme environmental conditions. OIE Reference Laboratories—one or more laboratories designated as centers of expertise on one of the animal or human diseases that OIE monitors—play an important role in disease surveillance and response. Altogether, OIE has established a network of more than 160 Reference Laboratories in 32 countries, covering 95 diseases. These labs can assist countries in the diagnosis of index cases, confirm laboratory results, provide training on diagnostic techniques, and provide other kinds of support in the management and control of disease. Tanzania is a resource-constrained country that faces challenges in establishing and sustaining laboratories, problems that many resource- challenged countries similarly encounter, and it is a critical country from an integrated human and animal health perspective. One third of the country is national park land, and it has great climatic diversity as well as exten-

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 SUMMARY sive interaction among livestock, wildlife, and humans. Tanzania has a long tradition of collaborating with international partners for its laboratories, but economic fluctuations and changing levels of funding have resulted in significant cutbacks to the laboratory system. Today, Tanzania’s new central veterinary laboratory has the capacity to deal with many emerging zoonotic and epizootic viruses and to diagnose a range of diseases. The country also has laboratories with traditional veterinary capacity. But Tanzania’s laboratories also lack sufficient equipment and trained personnel, and have not been able to fully comply with biosecurity and biosafety guidelines. All of these problems could be addressed with greater resources, but the government must address other challenges—such as hunger, widespread poverty, and need for educational improvements—in a very constrained economic climate. Despite the importance of animals and animal health to the macro economy (e.g., eco-tourism) and to individual livelihoods, these laboratories remain dependent on foreign donors. The U.S. CDC has focused significant attention on building labora- tory and epidemiological capacity in strategic locations that can serve regions with high threats but are low with resources. As part of a global strategy to monitor and respond to emerging infectious threats at the local, regional, and global levels, CDC has established the International Emerging Infections Program, which has five laboratories, located in China, Egypt, Guatemala, Kenya, and Thailand. The Kenya Medical Research Institute (KEMRI) laboratory in Nairobi was designed to establish diagnostic and epidemiological capacity, and it also conducts public health research and contributes to intervention strategies for high-impact diseases. The corner- stones of the program are surveillance, rapid response to outbreaks, training and building local capacity, and applied research. Its primary surveillance objectives are to identify and characterize emerging pathogens for human and select animal diseases, establish public health priorities in rural and urban settings, and provide a platform to evaluate the impact of interven- tions that have targeted high-priority diseases. KEMRI has a national reporting system that uses integrated disease surveillance and response, and also conducts sentinel surveillance in hos- pitals and refugee camps. To work around the lack of computer capacity in remote regions, it has also been promoting the use of cell phones and text messaging to collect disease rumors for investigation as more countries invest in cell phone technology. Through its surveillance program, KEMRI hopes to understand the incidence and prevalence of zoonotic and epizootic diseases in coexisting human and animal populations, the risk factors for humans and animals, and the potential of animal sentinels to provide early warning. Asia is another region with high population density, low resources, and high incidence of infectious disease. With half of the world’s population

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 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES and more than three-quarters of the world’s poultry living in South Asia, policies that work across political borders are of paramount importance in containing diseases there. The sheer population density in India and China places a tremendous burden on their public health systems, and public health for that region is important to the whole world. Asia is considered a disease hotspot because it is particularly fertile ground for zoonotic patho- gens to emerge both from wildlife and domesticated animals. Infectious diseases accounted for 25 percent of patient deaths in one of the region’s largest hospitals for tropical diseases. Within the United States, laboratories that provide veterinary diagnostic services are coordinated through the National Animal Health Laboratory Network. This network, created in response to a Department of Homeland Security directive, is designed to coordinate laboratory capacity at the state and federal levels for early detection of, rapid response, and appropriate recovery for animal health emergencies. The network currently includes partnerships with multiple laboratories, universities, and federal agencies. ISSUES Integrating resources that are dedicated to human health, animal health, and agricultural safety is a high-priority goal for many observers of this large and loosely linked animal and human disease surveillance network. Workshop participants also saw improved communication and information exchange as a goal, and mentioned that significant progress has been made. Yet building on the existing system and improving its cohesion and effectiveness would be challenging for several reasons. The sheer volume of information is so great that coordinating all of it may be not only unwork- able, but unnecessary. The existing systems were each created to serve a particular purpose; they have different missions and collect different kinds of information. Moreover, even within the United States, no federal agency has jurisdiction over the U.S. systems, and communication among them is imperfect. Authority for systems around the world is even more dispersed. Within any single country, there are a range of issues and needs, therefore differ- ent systems have been developed to meet them. The incentives for sharing information and the potential benefits and risks that different groups must consider are an important part of the picture. Governments or ministers with responsibility for human and animal health, agriculture, or finance may take into account the risk of severe economic disruption, unrest, or other consequences when a disease outbreak is announced, and disease surveillance programs must provide countries and officials with strong incentives (and perhaps protections) to participate.

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 SUMMARY While there are regulations in areas such as disease management, labo- ratory work, and species management, many are not followed particularly at the international level. Developing countries are not able to pay for surveillance efforts, and may lack sufficient funds for computers, a reli- able working electrical system, and access to the Internet. Thus multilevel communications are a challenge as data are not collected and reported, and information about evidence of disease or health practices is difficult to verify or disseminate. Developing countries may also lack human resource capacity to respond to an actual outbreak. Consequently, some regions are poorly represented in surveillance sys- tems, which are often hotspot regions with high likelihood of emerging dis- eases where surveillance is most needed. Many see the need to build capacity for sustainable, long-term surveillance and response as absolutely critical. Emerging infectious diseases are an integral aspect of larger concerns about global climate change and other environmental issues. Nevertheless, there has not been complete buy-in from the international community, and dis- ease surveillance is too easily viewed as an “old-fashioned,” smaller-scale activity by governments and other potential funders of surveillance efforts rather than a global public good. One risk of this semi-marginal status is that funding and attention come in the midst of a crisis, not in time for adequate planning, preparation, and protection. The compelling message is that sustained disease surveillance is a basic human and animal health neces- sity because ongoing interactions among humans, animals, and the environ- ment will inevitably lead to disease emergence or re-emergence, which has the clear potential to disrupt or destabilize societies, trade, economies, and hence, national security. Thus, building an understanding of the importance of and commitment to disease surveillance, and the capacity and resources to comply with existing guidelines, are essential to improving surveillance for emerging infectious diseases of zoonotic origin worldwide.

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