3
Current Surveillance Systems for Detecting Zoonoses in Animals

After exploring why surveillance is critically important, and the issues and challenges it poses, workshop participants discussed the existing surveillance systems throughout the world. Surveillance, which has been defined by the World Health Organization (WHO) 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,” may be conducted by institutions of various kinds (WHO, 2008a). These principles would also pertain to animal health surveillance. The presentations explored the current state of surveillance efforts for zoonotic diseases, with an eye to identifying gaps in their effectiveness and challenges for improving them. The discussion addressed several existing domestic and international surveillance systems and covered a variety of animal populations (see Appendix D for a table that provides a synthesis of these systems).

A new zoonotic disease 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 diseases that could threaten humans. Thus, 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.

THE GLOBAL EARLY WARNING SYSTEM

The review of animal surveillance systems began with a discussion of the Global Early Warning System (GLEWS), one of several current



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3 Current Surveillance Systems for Detecting Zoonoses in Animals A fter exploring why surveillance is critically important, and the issues and challenges it poses, workshop participants discussed the existing surveillance systems throughout the world. Surveillance, which has been defined by the World Health Organization (WHO) as “the system- atic 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,” may be conducted by institutions of various kinds (WHO, 2008a). These principles would also pertain to animal health surveillance. The presentations explored the cur- rent state of surveillance efforts for zoonotic diseases, with an eye to iden- tifying gaps in their effectiveness and challenges for improving them. The discussion addressed several existing domestic and international surveil- lance systems and covered a variety of animal populations (see Appendix D for a table that provides a synthesis of these systems). A new zoonotic disease 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 diseases that could threaten humans. Thus, 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. THE GLOBAL EARLY WARNING SYSTEM The review of animal surveillance systems began with a discussion of the Global Early Warning System (GLEWS), one of several current 

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 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES efforts to coordinate and build on existing surveillance networks. GLEWS, described by Stéphane de La Rocque of the Food and Agricultural Organi- zation of the United Nations (FAO), is a system for pooling information collected by FAO, the World Organization for Animal Health (OIE), and WHO. GLEWS was devised to improve the tracking of significant diseases among animals in high-risk areas, and to provide data analysis and early warnings to the international community. In place for only a year as of the June 2008 workshop, GLEWS was also designed to ensure that data collection efforts are shared among institutions and agencies, rather than duplicated. The program’s primary functions are disease tracking, informa- tion sharing, verification of threats, disease analysis, and support for urgent response to outbreaks. The GLEWS team has three working groups, each focused on a differ- ent aspect of the task: disease tracking, analysis and risk assessment, and response. The GLEWS team follows information available through a variety of channels to track rumors about diseases. They are currently monitoring highly pathogenic avian influenza (HPAI), Rift Valley fever, and foot-and- mouth disease; they hope to expand their operations to cover additional zoonotic and other diseases, such as African Swine Fever, rinderpest, and rabies. The GLEWS team mines a variety of media (such as the ProMED global electronic reporting system for outbreaks, the Global Public Health Intelligence Network, and AI-watch) as well as country reports and other data collected by FAO, and information from the European Commission, OIE, and agencies of the United Nations (including WHO, which has representatives in nearly every country in the world). The event tracking system includes a record listing each initial report, follow-up, actions taken, requests for assistance, and changes in status of the event. In collaboration with a variety of other centers with specific expertise, the GLEWS team analyzes the data collected in order to provide public health warnings in the form of long- and short-term forecasts. Based on this analysis, the GLEWS team puts out disease alerts, and also has the capacity to develop recommendations for coordinated responses to animal health emergencies and provide assistance to local authorities. The basic premise of GLEWS is that the team will never leave an event open; that is, they will track every rumor until they can either establish that it is not a risk or identify a clear warning that needs to be addressed and made public. Among the challenges for the GLEWS program, de La Rocque explained, is that of confidentiality. It is not uncommon for government officials to be reluctant to release information about a potential disease outbreak for fear of trade disruption or other reasons, and OIE is similarly unable to disseminate information unless it has been officially sent by the chief veterinary officer of their member governments. To address this prob- lem, GLEWS staff have established three levels of confidentiality to verify

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 CURRENT SURVEILLANCE SYSTEMS data they uncover from informal and official country sources. The top level of confidentiality classifies information sharing only among the three coordinating organizations (FAO, OIE, and WHO); the second level allows information to be disseminated with their collaborating centers; and the last level is for public dissemination. Establishing these levels of confidentiality allows information to be shared more readily between GLEWS partners without publicly disseminating information that has not been officially released by the country involved. In other cases, institutions and agencies in an affected region may have unclear lines of authority or conflict over roles and responsibilities. Thus, GLEWS is working to promote common guidelines that countries can use when faced with a potential outbreak. As of the June 2008 workshop, the GLEWS operation was in its infancy. STANDARDS OF THE WORLD ORGANIZATION FOR ANIMAL HEALTH As de La Rocque had noted, it is critical to have consistent standards and procedures applied across countries as an element of surveillance and response systems. Alejandro Thiermann of OIE described the standards that his organization has developed. The OIE has 172 member countries, and its objective is to engage each of them in a commitment to conduct surveil- lance, collect data, and rapidly disseminate data on both the presence of dis- eases being targeted as well as “other epidemiological events of an unusual nature,” Thiermann explained. Specifically, OIE’s objectives are to: • Encourage member countries to conduct surveillance and collect, analyze, and disseminate all animal health information necessary to mini- mize spread of disease in consistent ways; • Safeguard world trade by establishing health standards for animals and animal products, provide guarantees of the safety of animal food and protect animal welfare, and follow biological standards for diagnostic tests and vaccines; and • Provide expertise and encourage international solidarity in the con- trol of animal diseases, and improve infrastructure, the legal framework, and resources for veterinarians. The 172 member countries are legally obliged to adhere to the noti- fication obligations and the organization’s published standards, and OIE provides a variety of resources to assist them in doing so. A decision tree is used to determine which diseases are of concern and should be followed. The OIE has developed a web-based system, the World Animal Health Information System, for managing the data collected and providing addi- tional data resources. Each member country can add data, and the system

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 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES provides a simple and rapid method for countries to meet their reporting and other obligations. Maps and geo-coordinates assist with event location, and posted data are available to member countries. The OIE also offers other veterinary support services in 29 countries, including 160 reference laboratories and 20 centers for collaboration. In all, member countries have access to a staff of more than 130 experts covering 83 diseases. The OIE standards are designed to provide international guidelines that merge concerns about animal health and welfare, food safety, and public health. The OIE standards draw on the Sanitary and Phytosanitary Measures developed by the World Trade Organization, and are in harmony with those of other standard setting bodies such as the Codex Alimentarius (food safety) and the International Plant Protection Convention. The OIE standards include codes for: • Terrestrial animal health; • Aquatic animal health; • Diagnostic tests and vaccines for terrestrial animals; and • Diagnostic tests for aquatic animals. A process of regularly reviewing and updating the standards is integral to the system so that it can be adapted quickly as new information about a disease alters scientific consensus on the best procedures for responding to it. Thiermann closed with some observations about why the OIE system is so important. Its key principles—early detection, transparency, notifica- tion, and rapid response—depend on a combination of technical ability and political will, he explained. Thus, the challenge of improving and sustaining the effort is two-fold: encouraging countries to see surveillance as a global public good, and developing the necessary infrastructure to accomplish the task. The infrastructure may include laboratory networks, veterinary capac- ity, public- and private-sector involvement, informed farmers, and other factors. The OIE’s role is especially valuable when issues of international trade or competition among nations complicate questions of authority and responsibility. By mediating disagreements, providing objective analysis and procedural standards, and in many cases supplying the necessary infra- structure, OIE helps countries to view surveillance as a global priority and to do their part in supporting their own veterinarians, farmers, and other professionals in sustaining vigilance. WILDLIFE DISEASE SURVEILLANCE AND INVESTIGATION Although OIE focuses primarily on animals that are domesticated for food consumption, the health of wildlife is directly linked to that of both

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 CURRENT SURVEILLANCE SYSTEMS domestic animals and humans. Diseases among wild animals can also pro- vide early warnings of environmental damage, bioterrorism, and other risks to human health. Joshua Dein and Scott Wright, both of the U.S. Geological Survey (USGS), provided background on both surveillance of wildlife and the investigation of disease outbreaks in wildlife populations. Wright began by noting that the investigation of disease outbreaks among wildlife is a complex enterprise, involving not only many steps, but also many fields of expertise, as illustrated in Figure 3-1. The complexity begins with the significant variation around the world in the ways humans interact with different kinds of wild animals. A primary difference exists between cultures whose subsistence depends on agriculture and wildlife, and in which direct contact is thus a feature of everyday life, compared to more prosperous societies, in which interaction takes place primarily in the context of leisure activities. Because some subsistence economies are directly dependent on animals for survival, disease outbreaks among wildlife can have a dramatic impact under these circumstances. Yet these societies are least likely to have adequate (or any) infrastructure and expertise for animal disease surveillance particularly in wildlife. Wright stressed that the degree of support for investigation in any society depends on understanding Surveillance Epizootiology Microbiology Training, Field Parasitology outreach, investigation information and response Statistics/Modeling transfer Toxicology/Chemistry Veterinary Medicine Virology Wildlife Ecology Diagnostics Field and lab research FIGURE 3-1 Complexity of disease investigation in wildlife populations. SOURCE: Dein and Wright (2008). Figure 3-1.eps

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 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES the potential threats to human health, trade, local well-being, and national economies—there is little interest in potential threats to wildlife on their own. Both H5N1 and West Nile virus, for example, kill wild birds in very large numbers, Wright explained, but neither would have been likely to be investigated thoroughly if they had not had implications for human health. But waiting for connections to human health to show up may be too late, Wright explained. Diseases in wildlife often show up in the form of noticeable concentrations of carcasses, but these may not be noticed if no one is looking for them. In the case of marine life, dead animals may only be visible if they wash up on shorelines, but widespread die-offs in other wild populations may easily be missed as well. Even when an incident is noticed and reported to local officials, they may not recognize the significance of the incident or be aware of the steps they should take. Thus, the focus for those concerned with wildlife health is moving local information to the regional, national, and global levels—a considerable challenge. The approach to this challenge taken by the USGS National Wildlife Health Center, which is the only federal laboratory in the United States dedicated to wildlife disease investigation, is depicted in Figure 3-1. It is based on the premise that there are no mandates for reporting disease among wild animals, so the focus is on training and spreading the word through webcasts, podcasts, and other means to try to replicate the steps followed in veterinary and human medicine. Each step can yield a basis for research, Wright noted, and many diseases that are currently being studied were only recently identified through formal investigation. Few countries are in a position to conduct disease investigations in wildlife, Wright described, but he stressed the importance of wildlife disease investigation. Wildlife diseases may have profound effects on an ecosystem, or be evidence of threats to an ecosystem. Moreover, once a wild population has been depleted or eliminated, there is no mechanism for its replacement, as there would be for livestock. Wild populations can serve as reservoirs and hosts to diseases that also affect livestock and companion animals; although they can then be a vital link in a cycle that could also include humans, they are frequently left out of the surveillance picture. In Wright’s view, a truly effective wildlife disease prevention program is critical to protecting human health. He identified the following require- ments for establishing and sustaining such a program: • Greater awareness and understanding of the importance of wildlife health; • Substantial resources to build or improve capabilities; • Mandatory reporting for wildlife diseases; • Standardization of observations and reporting; and • A global clearinghouse for reporting.

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 CURRENT SURVEILLANCE SYSTEMS Some data are currently available from a number of sources, including data from international programs (e.g., FAO, OIE, Global Avian Influenza Network for Surveillance) which encompass only limited voluntary report- ing, and data from U.S. sources (federal-, state-, university-based) which are not coordinated nationally. Most local data, he explained, are located in file cabinets or desk drawers and are not being shared or used. Ideally, health data regarding humans, domestic animals, and wildlife should be coordinated. Dein picked up on the issue of available surveillance data to dem- onstrate the gaps in wildlife data. Figure 3-2 shows mortality for white males, and Figure 3-3 shows mortality for all terrestrial wild animals in the United States, respectively, both from the past 20 years. The gaps in the wildlife map do not necessarily indicate that no wild animals died in those U.S. counties during the period covered, but rather that there were no data reported or reported data were not available to the National Wildlife Health Center (NWHC). Similar reporting gaps exist in wildlife surveillance in countries around the world. To address them, the NWHC has developed a Wildlife Disease Information Node (WDIN) as part of the USGS National Biological Information Infrastructure. The goals for the program are to Age Adjusted Death Rate per 100,000 population 765.0 - 929.7 724.8 - 764.9 678.2 - 724.7 636.4 - 678.1 596.0 - 636.3 564.5 - 595.9 440.9 - 564.4 Hatching indicates sparse data Health Service Areas FIGURE 3-2 All-cause mortality for white males in the United States, 1988–1992. Figure 3-2.eps SOURCE: Dein and Wright (2008). bitmap color text replaced as text

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0 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES FIGURE 3-3 Wildlife mortality events, 1990–2008. Figure 3-3.eps SOURCE: Dein and Wright (2008). bitmap color build tools and resources within the wildlife health community and to con- nect wildlife data to existing surveillance systems for animals and humans, Dein said. The WDIN staff maintain numerous resources on a publicly available website, and also put out daily reports that summarize disease events. They also collaborate with other programs, including the Canary database of literature about animals as sentinels of human environmental health hazards. This database is maintained by the Yale School of Medicine and the Highly Pathogenic Avian Influenza Early Detection Data System, an avian influenza database maintained by the U.S. Departments of Agriculture and the Interior. Dein used the diagram shown in Figure 3-4 to illustrate the potential for cooperation among many agents involved with wildlife who could contribute to an ideal disease reporting system. Currently, he explained, an effort is underway to improve communication and approaches to this model for synthesizing U.S. wildlife disease data. The Wildlife Information System for Disease Observation and Monitoring (WISDOM) is being designed as a platform for both collecting wildlife disease data and disseminating it as

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 CURRENT SURVEILLANCE SYSTEMS International Surveillance State Resource Federal Resource Agencies Agencies National Surveillance Federal Wildlife State Wildlife Health Agencies Health Agencies Potential Wildlife Tribal Resource Local Resource Disease Agencies Agencies Reporting System Wildlife Public Rehabilitators Human Health Domestic Animal Agencies Health Agencies Veterinarians Physicians FIGURE 3-4 Proposed structure for a wildlife disease reporting system. SOURCE: Dein and Wright (2008). Figure 3-4.eps needed. At the same time, as has been discussed, OIE, FAO, and WHO are all contributing to wildlife surveillance internationally. Dein suggested, however, that the existing infrastructure is “minimal” and that the challenge is not just to increase awareness of the ways in which wildlife can affect the health of domestic animals and humans, but to broaden understanding of shared risk. He pointed out that new threats may come from a newly emerging virus or “some garden variety [pathogen] like tuberculosis or plague.” He closed with the observation that “a lot of [the] technological issues are more easily overcome than the people issues, and the mission issues,” such as the best way to share data, which data are most useful, getting permission to share them, and acting on them. EBOLA SURVEILLANCE IN NONHUMAN PRIMATES Targeted wildlife disease surveillance systems have been developed in response to several specific threats to human and animal populations as

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 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES well. One disease under targeted surveillance is Ebola, which causes wide- spread hemorrhages in nonhuman primates. Ebola has affected fewer than 1,000 humans (CDC, 2002), but its high fatality rate, as well as the threat it poses to endangered nonhuman primate species, has made the possibility of large-scale outbreaks a particularly chilling prospect. Pierre Rollin of the Centers for Disease Control and Prevention (CDC) described recent efforts to develop a surveillance system for Ebola fever in nonhuman primates, and some of the challenges that remain. Rollin began with an overview of some of the most notable outbreaks of diseases caused by filoviruses, which cause severe hemorrhagic fever in humans and other primates and include both the Ebola and Marburg viruses. The first case of Marburg on record was an outbreak in Marburg, Germany, in 1967. Ebola (named for a river in the democratic Republic of Congo) did not emerge in humans until 1976, when three outbreaks among humans were linked to contact with primates. A 1989 outbreak in nonhuman primates in a laboratory in Reston, VA, was detected because of an unusually high number of monkey die-offs and resulted in the euthanasia of 500 monkeys. Rollin mentioned that the outbreak was exacerbated by poor quarantine practices that enabled animal-to-animal transmission of Ebola, and this outbreak demonstrated how highly infectious the Ebola virus is and the vital importance of working with rigorous laboratory safety standards and husbandry practices. The Reston outbreak occurred among monkeys that had been imported from the Philippines for research pur- poses. Researchers were unable to trace the precise origin in the Philippines, though a single facility in that country was associated with several other outbreaks among nonhuman primates. Nevertheless, procedures for testing animals that are shipped, controlling infections, and conducting surveillance in these populations were put into place after that outbreak in Reston. Rollin outlined the reasons why surveillance of these diseases is so important, even though so few humans have been affected to date. Popu- lations of many nonhuman 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—and they are extremely susceptible to these diseases. 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 is very difficult, as many as 5,500 gorillas are estimated to have died from Ebola. Researchers have been eager to understand exactly how the disease spreads among these primates, and whether interaction among different species of nonhuman primates and possibly other species such as bats may play a role. The biggest question, Rollin explained, has been whether the virus is “spread from one area to the other like a big wave of an epi-

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 CURRENT SURVEILLANCE SYSTEMS demic, or whether you have a multi-emergence in different areas.” To help answer that question, a number of groups have worked together to set up a surveillance system called the Animal Mortality Monitoring Network in collaboration with the Gabonese and Congolese ministries of forestry and environment, and wildlife organizations including the Wildlife Con- servation Society (WCS), the Programme de Conservation et Utilisation Rationelle des Ecosystèmes Forestiers en Afrique Centrale, and the World Wildlife Fund. As is the case in so many disease surveillance contexts, with the variety of groups involved, coordination and other logistical challenges need to be overcome. Animal die-offs may be missed if carcasses in the wild are not noticed and reported, and the risk of infection from the carcasses is great. Because the carcasses decompose quickly, onsite investigation is very important, but special equipment and procedures are necessary to protect investigators from infection. Nevertheless, investigators have concluded that the incidence of Ebola in nonhuman primates is most likely caused by a combination of multiple, separate emergences and group-to-group spread of the disease. They have not yet been able to identify the reservoir for the disease, and Rollin indi- cated that recent results suggest the possibility that nonhuman primates are actually just accidental hosts for the pathogen. In any case, they serve as important sentinels for risk to local human communities, even though the risk of the disease spreading to other countries is small. GLOBAL SURVEILLANCE OF BATS Why are bats important from a surveillance perspective? Bats are car- riers for viruses that are harmful to humans—perhaps as reservoir hosts for Ebola, as Rollin hypothesized. Peter Daszak of the Consortium for Conservation Medicine (and a member of the workshop convening commit- tee), described his work and the work of his colleagues and collaborators on surveillance in bat populations. Daszak explained that 8 new zoonotic viruses that originated in bats have emerged since 1994 (see Box 3-1), and there is a significant potential for additional ones to emerge. Furthermore, Daszak added that understanding the ecology of host species is critical to evaluating risk of zoonotic disease transmission. There are more than 1,000 species of bats, and they are the most diverse of all mammals. One-fifth of all mammal species are a type of bat, and bats can be found all over the world, Daszak said. They are highly mobile and often well adapted to human environments, which means that they often share both food sources and dwellings with people. Human–bat interaction is quite common in developing countries such as Bangladesh and increasing as humans encroach on tropical forestland such as Sumatra.

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 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES BOX 3-1 Zoonotic Viruses That Originated in Bats Since 1994, with Year of Outbreak or Discovery 1994—Hendra virus 1997—Australian fruit bat lyssavirus 1997—Menangle virus 1999—Nipah virus 2001—Tioman virus 2005—SARS-like coronavirus 2005–06*—Ebola/Marburg virus 2007—Melaka virus SOURCE: Daszak and Epstein (2008). * PCR evidence published. Nipah virus, which emerged in swine and swine workers in Malaysia in 1999, illustrates why bats are so important. Investigators were initially puzzled by the connection between bats, pigs, and swine workers; they then conducted surveillance to better understand the pattern of disease transmis- sion. Researchers tested various bat colonies in Malaysia and determined that these fruit bats carried Nipah virus and that the virus circulated within these colonies. Using satellite collars to track bat movements in the region, they found that bats migrate across a broad range, leading researchers to discard the notion that the widespread outbreak was caused by human effects on the bats’ migratory patterns. They then turned their attention to the pigs that became ill from the virus and by coughing transmitted the virus to humans. Researchers concluded that fruit bats (reservoirs of Nipah virus) fed from orchards with swine farms, and the infected pigs ampli- fied and aerosolized the virus that consequently infected swine workers. Using mathematical models of a simulated outbreak, researchers found that outbreaks among swine workers and pigs occurred when migratory bats reintroduced the virus into a swine population that had previously been exposed and developed partial immunity, which allowed the epidemic to spread for a long time and essentially become endemic. This led to the realization that bats, while overlooked, will be important to study because they are high-risk reservoirs for zoonotic disease transmission. Thus, a clear surveillance challenge is to identify viruses with this kind of epidemic potential before they emerge or spread extensively. But finding such pathogens is tricky, to say the least. There are approximately 50,000

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 CURRENT SURVEILLANCE SYSTEMS vertebrate species, Daszak pointed out, with the conservative assumption that each might normally carry 20 unique unknown viruses, and translating into a global biodiversity of a million unknown vertebrate viruses, many of which are likely to be zoonotic. Currently, 2,000 viruses are known, so, Daszak noted, “we are underestimating the global diversity of viruses by 99.8 percent.” Moreover, the challenges of surveillance in bats are considerable. It entails collection of blood and other body fluids, which can be highly infectious, then testing the specimens by serology and viral culture, and recording the age and condition of animals. The collection of specimens must often be conducted in difficult, remote terrain, and it can be difficult to locate colonies. Bats are very sensitive to disturbance, and colonies may move in response to investigation. Furthermore, accurately identifying species can be difficult. Because it would be impossible to test every species of bat, the strategy must be to focus on so-called hotspots—areas with high biodiversity as well as high human population density—where zoonoses are most likely to be found. Jones and colleagues (2008) identified such hotspots in Figure 3-5. By conducting “smart surveillance,” researchers are able to target their resources and efforts in areas where human–animal interaction is most likely to provide conditions favorable to zoonoses. Daszak explained that the Consortium for Conservation Medicine’s sur- veillance efforts in wildlife species has been dependent on the work of local, FIGURE 3-5 Emerging infectious disease hotspots. Hotspots are indicated in red Figure 3-5.eps and include areas of high biodiversity and high human population density, which bitmap color may correlate to high connectivity between humans and wildlife. SOURCE: Jones et al. (2008). Reprinted with permission from Nature.

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 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES talented field workers and veterinarians at their field sites worldwide, and stressed the importance of building local laboratory capacity and the use of a central database available for scientists to coordinate future research. The Consortium has been working on standardized methodology for bat surveil- lance, and has been collaborating with colleagues from different disciplines to understand the ecology of potential host species in wildlife. SURVEILLANCE OF BUSHMEAT AND EXOTIC ANIMALS William Karesh of the Wildlife Conservation Society (WCS) picked up on the theme that surveillance of wildlife populations is important not only as an early warning system for diseases in humans, but also as part of an overall approach to sustaining the integrity of ecosystems worldwide. The WCS’s overall mission is the protection of wildlife and wild lands, and they also operate and oversee the Bronx Zoo and other animal centers. Thus, their mission also encompasses stewardship of captive wildlife, so they are able to conduct surveillance both in the wild and in controlled settings. Karesh’s focus was on surveillance of animals used for bushmeat, that is, meat of wild animals hunted for food. He noted that the demand for wildlife as a source of food has increased significantly in many areas, such as remote areas where workers are cutting down forest trees. Increased trade in wild animals, both legal and illegal, has also meant increased interactions between humans and wild animals, and increased opportunities for disease transmission. Karesh pointed out that the illegal trade has likely grown even faster than legal trade, though it is impossible to quantify. To give a sense of the scope, he noted that authorities had recently confiscated a planeload of 10,000 pounds of turtles being smuggled out of Indonesia. Many of the diseases humans contract from interacting with wildlife are easily preventable by following certain hygienic steps, particularly dur- ing animal handling and food preparation, but these disease prevention practices, Karesh said, are not well understood by those who rely most on bushmeat for survival. For that reason, educating and training local villag- ers on the importance of surveillance and ways to prevent infection of them- selves, family members, and neighbors have been a big focus of the WCS surveillance efforts. At the same time, populations that have daily contact with wild animals are in a good position to contribute to both surveillance and protection, so the WCS has worked to engage them in that effort as well. Above all, the goal of the WCS has been to encourage countries and local authorities to understand the importance of surveillance, and to build their own capacity to collect and analyze samples. Karesh used several examples to illustrate the ways diseases can emerge as a result of changing patterns of interaction between humans and wild animals. Severe Acute Respiratory Syndrome, for example, was linked to

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 CURRENT SURVEILLANCE SYSTEMS growing live animal markets in Asian nations (these markets are grow- ing in number and are found worldwide) where numerous animal species are housed together, each bringing different organisms into the mix, and expanding the opportunities for disease transmission. Karesh closed with a description of the Global Avian Influenza Network for Surveillance (GAINS), a project of the WCS that has been supported by CDC and the U.S. Agency for International Development since 2006. This effort is focused on monitoring information about the influenza virus in wild birds and sharing that information internationally. The program is a network involving partners in 36 countries, as well as web-based data and other resources. GAINS staff have worked to train others for data collec- tion and mortality investigations at the local level and then to compile data from colleagues around the world (the database is the WISDOM program described above). SURVEILLANCE OF INFECTIOUS DISEASES IN COMPANION ANIMALS Companion animals are excellent sentinels for emerging infections that can affect humans, in part because they are much easier to monitor than wild animals. Larry Glickman of the University of North Carolina at Chapel Hill described current procedures and challenges in this sector. He also cited other reasons companion animals are good sentinels. First, at least 170 million dogs and cats are kept as companion animals in the United States, generally in close contact with their owners. Companion animal ownership is just as common in other developed countries and is growing in many developing countries as well. Companion animals are reservoirs for zoonotic and parasitic diseases that are transmissible to humans, such as leptospirosis, and Glickman speculated that companion animals may be more sensitive to a fixed pathogen dose. They are also highly susceptible to several biothreat agents of concern. Table 3-1 lists some biothreat agents that may occur naturally in companion animals. Recognizing the importance of monitoring companion animals, Purdue University and Banfield®, The Pet Hospital, with funding from CDC, col- laborated to sponsor the National Companion Animal Surveillance Pro- gram (NCASP). Glickman explained that the program’s broad focus was designed to address a range of health events in companion animals. Specifi- cally, the program can provide: • Real- and near real-time information on health-related events among companion animals in the United States; • Detailed statistical analysis to identify space–time clusters of events and characterize host and environmental risk factors;

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 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES TABLE 3-1 Biothreat Agents in Dogs and Cats Category A Disease/Agenta Occurs Naturally Inb Anthrax (Bacillus anthracis) Dogs and cats Botulism (Clostridium botulinum toxin) Dogs and cats Plague (Yersinia pestis) Cats and dogs Smallpox (Variola major) Not documented Tularemia (Francisella tularensis) Cats and dogs Viral hemorrhagic fevers (filoviruses and arenaviruses) Not documented aCategory A diseases or agents refer to pathogens that are rarely seen in the United States but are considered high-priority agents because they pose a national security risk. bSpecies of greatest or equal susceptibility listed first. SOURCES: CDC (2003); Glickman (2008). • Alerts to the occurrence of potential acts of bioterrorism, emerging zoonoses, and toxic chemical exposures; • Syndromic surveillance and multihazard situational awareness; • Potential to adapt to chemical spills and contamination from toxic waste sites to monitor both acute and chronic health outcomes; and • A resource for pharmacoepidemiological research. NCASP maintains a database that enables it to respond quickly to an event, such as Hurricane Katrina, by comparing illness outbreaks to baseline data. The partnership with Banfield®, The Pet Hospital, provides access to standardized and computerized medical records from more than 3.5 million annual veterinary patient visits in 49 states and all major U.S. population centers. Each animal’s unique identifier number makes it pos- sible for investigators to track disease events by neighborhood, as well as to track lab results and other health information and obtain biological specimens when necessary. The kinds of data collected include 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. The Banfield® system also streamlines com- munications with veterinarians, for example, by sending an alert that when making a diagnosis of a flu-like illness, they should collect and submit a specimen for testing according to protocols provided. “We can then identify those pathogens,” Glickman explained, “map the geographic occurrence, and share that information with our colleagues in epidemiology at the state health department, but also with others who might need to know, such as the makers of influenza vaccines.” NCASP monitors influenza-type illnesses in dogs, cats, and birds, which may bring H5N1 into the United States.

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 CURRENT SURVEILLANCE SYSTEMS Companion Emergency Animal Room (INPC) (Banfield) Pharmacy Livestock Sales (BOAH) Data Collection, Contingency, Evacuation, Wild bird (USDA Interdiction Planning, APHIS) Surge Modeling Data Integration, Privacy Preservation, Collection, Interdiction, Pandemic/ Schema, Lineage Evaluation, Response Planning & Biosurveillance Statistical, Text, Sensor, Evaluation, Responder C&C and In- Geospatial Analysis, Factor Training, Scalable field Monitoring and Correlative Analysis, Simulations C&C and In-field Visual Analytics Investigate, Quarantine, Control, Treat, Evacuate FIGURE 3-6 Ideal data integration from multiple animal species. SOURCE: Glickman (2008). Figure 3-6 (replaced) They are also interested in vector-borne pathogens, so they have a system R01393 for collecting information on the occurrence of fleas and ticks in the com- panion animal population, and collect specimens when needed. The goal for NCASP is to integrate the data from animal species and humans, as shown in Figure 3-6. However, Glickman explained, a long- term investment will be needed to fully integrate animal data sources just within the United States (including private and state-run veterinary practices, diagnostic laboratories, and surveys). This investment would not include integration with human health data, or expanding such a system internationally. DISCUSSION Discussion of the overall picture of animal surveillance opened with the observation that the presenters, representing various sectors, had not previously had the opportunity to meet and collaborate as a whole group. Although many had previous contact with one another, they agreed that

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0 GLOBAL SURVEILLANCE OF ZOONOTIC DISEASES the full breadth of the human and animal surveillance enterprise is not ordinarily addressed in any one venue. The challenges of coordinating this large and loosely linked network were a key topic. Coordination For the question posed by the committee regarding the multitude of disease information systems, participants offered a number of reasons why international human and animal disease surveillance systems are not more coordinated. One participant noted that each of the existing systems were all created for very different reasons, each with different missions. They also collect different kinds of information, so it is a challenge to “pick the parts that are going to interface.” Part of this interfacing problem is terminology—“What do you call species? What do you call an age class? What do you call a disease?” One participant observed that these questions complicate information sharing. Information technology issues can pose another obstacle, and although they are potentially solvable, developing compatible systems requires not only the will but also, often, a significant amount of work, resources, and time. Coordination also requires confidence and trust, others noted. “You have to go step by step and have some success stories to show that you are not just trying to get data and to do your own business,” one partici- pant asserted. In order to cooperate with organizations that may be based around the world, for example, people need to understand the importance of the effort and the vital role they can play. Lack of Mandate for Overall Coordination Perhaps more important, a participant offered, is that “what we don’t have is a group of individuals, an agency, or an institution that looks at the overall picture across human and animal populations, looks at the current surveillance system, the information that each provides and how they link and how they either complement, synergize, or have no relationship with each other.” No federal agency has jurisdiction over multiple systems, and it was noted that companion animals may be the only group not overseen by any federal agency. It was suggested that what is needed is not, perhaps, a super agency, but rather a super group that tries to answer some of these questions and provide coordination and linkages, rather than put together piecemeal approaches to deficiencies within individual systems. Participants noted that regulations exist in areas such as disease man- agement, laboratory work, and species management, but many are not followed particularly at the international level. Therefore, as many discus- sants pointed out, building an understanding of the importance of disease

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 CURRENT SURVEILLANCE SYSTEMS surveillance may be more fruitful than expanding regulatory authority. Moreover, several participants observed, the mandate or requirement is in many cases less important than making sure that the capacity and resources to comply are in place where they are needed. “If you look just in the United States, the number of state and federal wildlife people who are out in the field on a daily basis have a huge amount of information that they could provide. They don’t have the resources to do it. They don’t have the time to do it, though they would have no objection to providing those data.” Targeting the Effort A related issue was the importance of focusing whatever efforts could be made in the areas of greatest need. As one participant noted, “There are some tremendous things going on in sampling the wildlife population worldwide now, but really when you compare that to the biodiversity that is out there, you could be sampling millions and millions and millions more animals.” A key strategy is education—“getting folks to understand where the information is useful.” Another noted, “We are depending on biologists who go into caves and work with bats to tell us there is a [greater] die-off going on compared to what they normally see, and trying to train them to understand baseline mortality versus something unusual and then call us and consult with us, and we will work with them to try to figure out where to go next.” Providing the mechanisms, incentives, training, and resources to people who are on the ground and have the opportunity to observe health events in animals is perhaps the best platform on which to build a comprehensive, internationally linked system. Some observed that a significant infrastructure is in place, and needs to be better coordinated, but others pointed out that sustaining the effort remains a challenge. One participant noted: “I have seen it so many times. You set up the surveillance system and there’s some donor funding, some exterior funding. That stops and the thing collapses—that is clearly not the way we want to do it.”

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