Global%20disease

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Global%20disease

  1. 1. Global Disease surveillance, emerGent Disease PrePareDness,Author(s)—Running Head 1 anD national securityCarleton J. Phillips, Anne M. Harrington, Terry L. Yates, Gary L. Simpson, and Robert J. Baker
  2. 2. Cover: Earth from space, photo courtesy of NASA. Upper left, Drs. John Hay (University of Buffalo, New YorkState Center for Bioinformatics) and Roger Hewson (Health Protection Agency, Porton Down, United Kingdom)conducting zoonoses fieldwork in Central Asia with authors Phillips and Baker, photo by R. J. Baker; upper right,Carios kelleyi, a tick and potential vector parasitic on bats, photo by Jim Gathany courtesy of CDC; lower left,the deer mouse, Peromyscus maniculatus, a rodent that carries hantavirus in the United States, photo courtesy ofCDC; lower right, two CDC microbiologists, Drs. Thomas Stevens, Jr. and Amy Hartman, preparing for work ina BSL-4 facility, photo by Jim Gathany courtesy of CDC.
  3. 3. Global Disease Surveillance, Emergent Disease Preparedness, and National SecurityCarleton J. Phillips, Anne M. Harrington, Terry L. Yates, Gary L. Simpson, and Robert J. Baker Museum of Texas Tech University Lubbock, Texas
  4. 4. Layout and Design: Lisa BradleyCover Design and Plates: Carleton J. PhillipsCopyright 2009, Museum of Texas Tech UniversityAll rights reserved. No portion of this book may be reproduced in any form or by any means,including electronic storage and retrieval systems, except by explicit, prior written permissionof the publisher.This book was set in Times New Roman and printed on acid-free paper that meets the guidelinesfor permanence and durability of the Committee on Production Guidelines for Book Longevity ofthe Council on Library Resources.Printed: December 2009Library of Congress Cataloging-in-Publication DataGlobal Disease Surveillance, Emergent Disease Preparedness, and National SecurityCarleton J. Phillips, Anne M. Harrington, Terry L. Yates, Gary L. Simpson, and Robert J. BakerISBN 1-929330-19-7ISBN13 978-1-929330-19-5Museum of Texas Tech UniversityLubbock, TX 79409-3191 USA(806)742-2442This publication is available free of charge in PDF format from the website of the Natural Science ResearchLaboratory, Museum of Texas Tech University (www.nsrl.ttu.edu). The authors and the Museum of TexasTech University hereby grant permission to interested parties to download or print this publication for personalor educational (not for profit) use. Re-publication of any part of this paper in other works is not permittedwithout prior written permission of the Museum of Texas Tech University.
  5. 5. Global Disease Surveillance, Emergent Disease Preparedness, and National Security is in-tended to provide background information and integrate a wide variety of scientific and technicalsources relevant to strategic planning. Policy- and decision-makers in government comprise oneintended audience, but we also believe that our paper will be valuable to citizens interested ininfectious disease and its impact on society, economy, and security. With the foregoing in mind,this paper does not present a comprehensive review of the vast literature on the subject, and weapologize in advance to authors whose papers might not be cited. The opinions, conclusions, and recommendations presented here are entirely the responsibil-ity of the individual authors and may not be construed to represent any agency or any policy ofthe United States Government. All of the materials used in writing this paper, both those formallyreferenced and those that were used as general background but not cited, are publicly available.
  6. 6. Authors’ Note As our monograph went to press, the attention of the global community was fixed on a pandemic outbreakof influenza A, H1N1. This outbreak is an example of the currency of the ideas expressed in our monograph. Acentral concept is that human morbidity and mortality must be continuously monitored, analyzed, and understoodin context of dynamic interactions and perturbations of ecosystems that affect the health status of wildlife popula-tions and biodiversity and threaten the economic stability of agriculture. The reality that approximately 60% ofthe estimated 1,461 known infectious diseases of humans infect both humans and other animal species, and thereality that 70-80% of emerging infectious diseases of the past 30 years have been of zoonotic origin, underscoresthe relevance of this perspective to human health and biosecurity. The following highlights serve to illustrate how the influenza A, H1N1 outbreak can be viewed and assessedin the framework of our monograph. Global infectious disease surveillance—In June 2009, the date of onset and exact origins of H1N1 remainedunclear. Early event detection would be favored by implementation of a worldwide, systematic, syndromic sur-veillance system of known (or measurable) sensitivity and specificity. Because of the dynamic interactions ofinfluenza viruses in humans, domestic animals, and wildlife, surveillance must span all of these species if it is toserve as a global biosecurity defense system. Laboratory diagnostics—The absence of sophisticated, regional, diagnostic laboratories delayed virtuallyevery aspect of the response to what became a global pandemic. Laboratory diagnosis of infectious diseasesremains the “gold standard” of surveillance, although timeliness may be measured in days, weeks, or months. Situational awareness—Understanding the susceptibility of any host species to a newly recognized andevolving influenza virus requires knowledge of age-specific seroprevalence in all species at risk. This will con-stitute a major challenge for the world community in coming months and years. Molecular biology and genomics capabilities—The disciplines of molecular biology and evolutionarybiology, in particular, are providing insights about the origin of the outbreak, the nature of transmissibility, theimplications of a triple-reassortant influenza, and the virulence of the pandemic strain. One regrettable con-sequence of the contemporary characterization of the outbreak strain as a ‘triple-reassortant’ influenza A viruswhose genome has human, swine, and avian genes (originating on at least 3 continents) has been the speculation(by some observers) that this is an engineered virus and that the outbreak is the result of an intentional release.Fortunately, this suggestion has been thoroughly debunked by the time of this writing. Global data sharing—This issue is arguably the most important to the success of worldwide outbreak in-vestigations. The contrast in the multinational transparency of data to the experience of the first global epidemicof the 21st Century (SARS) is notable. This success possibly is due to International Health Regulations institutedin 2005. Public health, social, political, religious, diplomatic, and economic implications—The forced quarantineof foreign nationals is one example of a response with legal implications. Bans on importation of Mexican andU.S. pork products are examples of commercial impact on trade. A complex political and social impact occurredin Egypt because a government order to slaughter all swine affected the Coptic Christian minority, which led toclashes with police. A different kind of impact was felt in Mexico, where it was estimated that during the peakof influenza activity, Mexico City lost an estimated $57 million per day in tourism and other revenues. Finally, i
  7. 7. iithe general impact of the H1N1 virus can be described by the so-called “Katrina syndrome,” which holds that anymajor disaster or public health emergency will predictably expose social disparities in a population or society. In June 2009, the Robert Wood Foundation (with Trust for America’s Care and the Center for Biosecurity)released a report on pandemic flu preparedness (available at http://healthyamericans.org/report/64/pandemic-flu-frontlines), which is consistent with themes covered in our monograph. Examples from the H1N1 experienceinclude: inadequate resources at public health departments; the health care system was overwhelmed; communi-cation was not well coordinated; WHO pandemic alert phases caused confusion; and international coordinationwas more complicated than expected. As we explain, such problems and short-comings would be expected basedon the complexity of global disease surveillance in a biosecurity context.
  8. 8. iii Contents Executive Summary 1I. Introduction 3 Challenges to Global Disease Surveillance 5 An Accidental Confluence of Significant Events 7 Section Summary 9II. The 2000 National Intelligence Estimate 11 The Deadly Seven Diseases 11 Animal-borne Diseases 12 The Role of Emergent Disease According to the NIE 14 Section Summary 16III. Global Disease Surveillance: Problems and Concerns 17 Diagnostics 18 Information Gathering 19 Emergent Disease, Reservoirs, Vectors, and Geographic Hotspots 19 Disease Selection and Surveillance Systems 22 Section Summary 23IV. Intentional Disease—A Significant Layer of Complexity in 25 Disease Surveillance The Role of Technological and Scientific Advances 25 Section Summary 27V. Mining Nature for Biological Weapons 29 Understanding the Soviet Zoology Paradigm 29 The Soviet Anti-plague System—A Model for Mining 31 Lessons Learned about Mining and Disease Surveillance 34 Section Summary 35
  9. 9. ivVI. Disease Surveillance, Biological Weapons, and 37 Transnational Terrorists Section Summary 39VII. Nonproliferation, Threat Reduction, and Disease Surveillance 41 TADR—A Threat Reduction Version of Disease Surveillance 42 Section Summary 44 PLATES I-VIIIVIII. Emergent Disease, Geospatial Databases, and Reservoir Species 45 Technical Perspective on Emergent Disease 45 Historical Factors, Infrastructure, and Preparedness 50 Preparedness versus Post-outbreak Response 51 Infrastructure for Preparedness 52 Section Summary 54IX. The Way Forward 57 Section Summary 61 Acknowledgments 62 References and Notes 63 Key to Abbreviations and Acronyms 71 Index 75
  10. 10. Global Disease Surveillance,Emergent Disease Preparedness, and National Security
  11. 11. Executive Summary In March 2006, the White House released The National Security Strategy, which recognized that naturalpandemics pose a risk to social order great enough to necessitate new public health strategies and responses.Moreover, this same document—and other recent government agency and congressional reports—also recognizedthe grave threat to national security posed by transnational bioterrorism, intentional disease outbreaks, or evenaccidental release of pathogens from laboratories not compliant with biosecurity protocols. Additionally, it isincreasingly obvious that emergent zoonotic (animal-borne) diseases pose a general threat with implications forinternational cooperation and social and economic stability. Such outbreaks might increase over time becauseclimate change, human population density, land use, and anthropogenic modification of habitat all contribute tothe likelihood of zoonotic infectious agents entering the human population. Global disease surveillance—the ability to detect, identify, and monitor disease on the broadest geographicscale—is a critically important challenge with political, social, and economic overtones for the United States andthe international community. In theory, global disease surveillance could provide an important foundation forstrategic response to natural outbreaks as well as to intentional or accidental misuse of infectious agents. And atthe very least, a system of global disease surveillance could detect anomalies in prevalence of infectious diseasesin human populations or in their livestock and in this way could trigger an appropriate, coordinated response. The basic infrastructure for disease surveillance exists and versions of it are successfully functional withinmany nations. National systems thus contribute invaluable data for government planning and response in boththe human and animal health sectors. In terms of international infrastructure, many organizations including UN-associated agencies and NGO’s, already either monitor infectious diseases on a broad scale or provide assistancewhen outbreaks occur. At the same time there is no overall international coordinating leadership that covers both‘human’ and ‘animal’ diseases, no centralized accessible system of databanks, and relatively few multilateral orbilateral agreements for data sharing. Implementation of an international system will require significant diplomacy,although it might be argued that the outcomes will warrant the effort. Improved biosecurity is one example. On a global scale, diagnostic resources and reliability are highly variable. This especially is the case inregions that are economically depressed or politically unstable. International response to outbreaks can be swiftand potentially effective on a high profile case-by-case basis (such as with influenza A, H1N1), but is incapableof responding to the broad range of public or animal health issues that arise regularly. Unanticipated outbreaksinvolving previously unknown zoonotic agents add yet another type of complexity that demands a well-coordinatedresponse and transparent international data sharing. Historical experience documents the potentially dangerouspolitical impact of natural outbreaks that occur by chance in regions of conflict or in regions that are socially oreconomically unstable. Intentional outbreaks of disease or the potential for outbreaks that are the consequence of incompetentlaboratory practices are matters of special concern. A disease surveillance system should be able to detect anddistinguish such events, but currently it is unlikely that unnatural outbreaks would be recognized quickly. A globaldisease surveillance system could contribute to United States national security by serving as a stabilizing forcein the face of a pandemic. At the same time, it might be too much to expect that a global system could recognize‘unnatural’ events that could destabilize nations or large geographic regions. The fact is that too little is known about the geospatial distribution, ecology, and biology of zoonotic diseasesthat have the potential to cause outbreaks in human populations or in the agricultural sector. Intensive research 1
  12. 12. 2 Global Disease Surveillance and National Securityover the past several decades has produced a substantial amount of information that substantiates the value ofknowing about the geographic distribution, genotypic characteristics, and evolution of infectious agents. Therealso is substantial value in data about reservoir species and vectors. Mathematical modeling and remote sensingby satellite have advanced to the point where it is practical to monitor vast areas and predict outbreaks. Our recommendation is that Emergent Disease Preparedness must be a high national security priority forthe United States. The development of an accessible database with global coverage is practical, and would serveas the foundation for monitoring, assessing, and responding to outbreaks, especially outbreaks of unknown ori-gin. Moreover, an Emergent Disease Preparedness Program would shift strategic focus from defense against theunknown to active engagement and acquisition of scientific information essential to security. The program thatwe envision will serve as a logical vehicle for international cooperation in biosecurity. It will create diplomaticpathways to agreements that support science, medicine, and disease surveillance. Finally, from our perspective,such a program can be seen as a maturation of nonproliferation and threat reduction strategic thinking in the fieldof biological sciences.
  13. 13. Introduction 3 I. Introduction Global disease surveillance—the ability to de- can have serious consequences for the United States (6,tect, identify, and monitor the occurrence of disease 7, 8). Several foundations privately fund one zoonoseson the broadest geographic scale—is a critically im- surveillance system, called the Global Viral Forecastingportant challenge with political, social, and economic Initiative (GVFI) (9). The United States Department ofovertones for the United States and the international Defense also has a surveillance system for emergingcommunity (1). infectious diseases—the DoD-GEIS (10). The basic concept of ‘surveillance’ is not new. Unfortunately, disease outbreaks also can be in-In 1968, prior to the age of molecular diagnostics and tentional, and the threat of transnational bioterrorismpowerful desktop computers and associated software, or even state-sponsored programs is a significant factor.the Centers for Disease Control (CDC) defined surveil- Disease outbreaks also could be the accidental conse-lance as “ongoing systematic collection, analysis, and quence of human manipulation of nature or even stan-interpretation of health essential to the planning, imple- dard types of research on infectious agents conductedmentation, and evaluation of public health practice (2).” without adequate biosafety practices. The collectiveAlthough not mentioned in this definition, the pathways national security significance of disease outbreak isof dissemination of acquired information or analysis multiplied by the potential for intentional outbreaksis an essential aspect of surveillance. One obvious to be masked as natural disease (11, 12). Under mostpathway is in the form of feedback to persons generat- circumstances it would be difficult for a nation to knowing the initial surveillance data. This is the pathway if they were under attack or facing natural phenomenathat ensures that disease surveillance does not become (13). Appropriate response to a disease outbreak ofmerely a ‘collection’ and ‘archive’ process. unknown origin thus is a major challenge, which begins with surveillance and detection (14). Unfortunately, our In the broad sense, surveillance programs can be ability to respond and distinguish between natural andapplied to an array of health-related subjects ranging intentional outbreaks is limited by an absence of criticalfrom infectious disease to occupational safety, injuries, surveillance information on a global scale.and personal health practices. Over time, four types ofsurveillance have been applied to monitoring diseases: On a global scale, disease surveillance is an ex-active, passive, sentinel, and syndromic. Among these tremely large challenge. The international complexi-types of surveillance, syndromic surveillance typi- ties are daunting. They include: working relationshipscally makes use of spatial (geographic) and temporal among international organizations with overlappinganalyses. One example is the Syndrome Reporting jurisdictions; parochial, political, economical, andInformation System (SYRIS), which can provide an security interests of neighboring states; difference inearly warning to important disease outbreaks or bioter- average levels of education; access to adequate train-rorism events (3). ing and equipment within a particular country; and the reality that in some countries there simply are higher Regardless of the surveillance system, the signifi- priorities, such as adequate food supplies, clean drink-cance of global disease surveillance to United States na- ing water, and basic sanitation.tional security policy arises in part from the appearanceof emergent or re-emergent zoonotic (animal-borne) Regardless of complicating factors, many fun-diseases in human beings (4, 5). Most emerging infec- damental mechanisms for global disease surveillancetious diseases in the past 40 years have had a zoonotic are in place and functional. In the United States, theorigin. Such outbreaks can be natural phenomena. Centers for Disease Control detects, monitors, and re-Habitat modification, geographic changes in human ports on disease outbreaks in humans. A recent (2006)population densities and land use, and climate change restructuring within CDC reflects the importance ofare examples of factors that can affect natural outbreak. emergent zoonotic diseases. Likewise, the AnimalEconomic and social factors interrelate with the forego- Public Health Information System (APHIS) within theing factors. But regardless of cause, zoonotic diseases Department of Agriculture monitors animal health—
  14. 14. 4 Global Disease Surveillance and National Securityespecially livestock and poultry, but also wildlife to cant to livestock in a particular geographic setting. Thea limited extent—on a global scale and maintains a OIE database is called the World Animal Health andgeospatial database of disease occurrence. Zoos are Information Database (WAHIS). The FAO Animal Dis-important sentinel sites. These institutions typically ease Information System database is called EMPRES-imonitor the health of their animals on a regular basis. (17). These systems trigger an alert that includes diseaseIn the United States, state environmental and conserva- diagnostic information and geographic data. The OIEtion agencies monitor and report on wildlife diseases, missions are to: ensure transparency of global animalespecially in game species frequently in contact with disease monitoring; disseminate animal disease reportshuman beings. and veterinary information; improve methods of disease control and eradication; and publication of standards Several national laboratories are positioned to for international trade in animals and animal products.respond to outbreaks linked to potentially exotic infec- The Federation of American Scientists developed atious agents. Although the trend is generally uncoor- policy program for monitoring emerging diseasesdinated, academic institutions are gradually improving (called ProMED), which includes projects aimed atresearch facilities (typically by building BSL-3 labora- using disease surveillance as a mechanism for detectingtories) and monitoring the health of faculty, students, agro-terrorism or economic sabotage potentially on aand technicians who work with animals or infectious global scale (18).agents. The National Institutes of Health (NIH) hasfunded Regional Centers of Excellence for Biodefense The World Bank and a variety of non-govern-and Emerging Infectious Disease Research, which in mental organizations (NGO) contribute to aspects ofturn fund research and career development and attract disease surveillance through loans or local medical as-scientists into work that is relevant to both biodefense sistance or data gathering and dissemination. In someand response to emergent diseases (15). All of these re- countries, World Bank funding has been leveraged insources are intended to be part of the network foreseen order to develop political will and commitment fromas a component of the National Biodefense Analysis governments previously disinterested in infrastructureand Countermeasures Center (NBACC) (16). necessary to support disease surveillance. All developed countries and a substantial number The United States maintains bilateral agreementsof small, less economically developed countries have on joint disease surveillance projects through agenciesgovernment agencies analogous to those in the United such as the United States Agency for InternationalStates. Many countries exchange at least certain types Development (USAID), the Department of Healthof health information. A good example is the network of and Human Services, the Department of Defense, andnational and international information systems devoted the Department of State. The US-Japan Commonto tracking the annual outbreak of influenza. Many Scientific Agenda and EU-US task force on emergingcountries also link into central reporting databases such diseases are two additional platforms that support dis-as the one maintained by APHIS in the United States. ease surveillance. Finally, Article X of the BiologicalOn an international scale, the World Health Organiza- Weapons Convention (BWC) provides incentive fortion (WHO) has the major role in monitoring diseases in countries to team on epidemiological research andhumans. WHO also responds to selected international surveillance (19). This latter system has potential valueissues, including fielding teams of experts in response as a mechanism for addressing disease outbreaks, al-to outbreaks, linking countries to sources of financial though it also requires that the outbreak is suspicious.aid, and providing training and technical assistance This requirement in itself creates yet another layer ofwhere needed (1). In a similar way, the World Organiza- political complication, which might limit the usefulnesstion for Animal Health (formerly Office International of the BWC as a mechanism for international responsedes Épizooties) (OIE) in Paris and the UN Food and to an outbreak (20).Agriculture Organization (FAO) monitor and collectinformation on animal (generally livestock) diseases on In the overview, the mere concept of global dis-a global scale. The OIE is linked to numerous regional ease surveillance is both ambitious and complex. Someorganizations that usually emphasize diseases signifi- of the complexity comes from the variety of organiza-
  15. 15. Introduction 5tions and divergent missions that in some way are a diseases, and the potential intentional use of diseasepart of disease surveillance. Political and economic agents as weapons is a significant security issue forrealities add another layer of complexity. Moreover, the United States (12).the nexus of disease surveillance, emergent zoonotic Challenges to Global Disease Surveillance Although fundamental technology and models contact with human beings. Herds of livestock, flocksfor disease surveillance exist, the current system is of poultry, or pets kept by humans provide infectiousinadequate for the task on a global scale, especially in agents with opportunities to multiply rapidly in prox-context of United States national security. The reality imity to humans. Rapid multiplication in a new hostis that national security is a priority. Because disease environment creates a situation in which new geneticoutbreaks could result from intentional misuse of strains are likely to appear. Outbreaks in humans canbiology or even carelessness in research laboratories, follow. Many nations have struggled to respond todisease surveillance and United States national security complicated pandemic threats such as avian influenzaare overlapped. But the perspective, priorities, and and SARS, but politics, suspicion, and self-interestgoals of the United States are not necessarily shared complicate cooperation and collective planning.with all nations that might participate in a ‘global’surveillance system. One of the most basic challenges, In the foregoing examples, purely technical is-therefore, is to overcome such differences in perspec- sues also complicated the international response totive and priority. Engagement through the diplomatic outbreaks. In the case of SARS, the initial focus wascommunity is a significant aspect of developing any on Chinese rural markets but the identity of the wildtype of global system. reservoir species was unknown. Establishing rhinolo- phid bats as the ultimate origin of SARS required a The purely scientific complexities of emergent combination of basic biological fieldwork, systematicdisease, the absence of critically important baseline mammalogy, and laboratory research. In the case ofinformation, the international variability in diagnostic avian influenza H5N1, an understanding of the rolecapability, the realities of international politics and of migratory bird species and their interactions withpolicy, the shared concerns over biosecurity and dual domestic fowl is incomplete. Another complication isuse capabilities, the involvement of the private sector, posed by the fact that strains of avian influenza H5N1the facts of recent East-West history, and the limita- virus also have infected house cats in both Thailandtions on coherent strategic planning and leadership all and Iraq. Analysis of an infected cat obtained in Iraqcombine to make disease surveillance an enormous revealed that the strain of H5N1 was 99% similar to achallenge on a global scale. previously sequenced strain obtained from geese. Phy- logeography is an analytical tool that enables scientists The spread of avian influenza H5N1, the appear- to combine a genealogy of viral strains with geographicance of a previously unknown syndrome (SARS-related locations from which the strains are known to occur.coronavirus), and outbreaks of human encephalitis Using this tool, scientists placed the cat-derived viralcaused by Nipah virus in south-central and southeast strain isolated in Iraq in Clade II of H5N1 viruses. OnAsia remind us of the dangers posed by lurking infec- this basis the Iraq strain was geographically associatedtious diseases and the rapid mutation rates that will with viruses circulating in geese in Qinghai, China (25).always produce new strains (21, 22, 23). In all three How a cat in Iraq contracted this strain of H5N1 virusexamples, the pathogens originated in wild animal ‘res- is unknown, at least in an exact sense. Most likely,ervoir’ species and spilled over into domestic animals H5N1 entered northern Iraq in poultry, probably via the(24). Introduction of an infectious agent from wild spe- outbreak that occurred in Turkey. In the meantime, thecies into domestic animals can result in a crisis because phylogeographic analysis that revealed the connectiondomestic animals often are densely congregated and in between the virus in cats and Qinghai, China, illustrates
  16. 16. 6 Disease Surveillance and National Securitythe value of linking nucleotide sequence data in both a scientific foundation, is to seek an accurate understand-phylogenetic and geographical context. Such a linkage ing of the actual species that act as reservoirs. The termprovides information known as a “DNA/RNA postal ‘wildlife’ connotes a level of uncertainty and providescode” and it is a powerful tool for tracking, predicting, such a low level of information that it is useless whenand understanding zoonotic diseases in a geographic it comes to prediction of ecological distribution, orcontext (26). Phylogeographic analysis of nucleotide monitoring of population densities and dispersal, orsequences—be they DNA or RNA—can be applied responding quickly to an outbreak. Currently avail-to infectious agents, their reservoir species, and any able laboratory and field technologies can result invectors involved in transmission. Combinations of genetically-based species identifications. Preparednesssuch data can reveal historical and evolutionary inter- for responding to outbreaks would be significantlyrelationships among zoonoses and hosts and is a basic improved if baseline data on reservoir species, theirstep toward predictive models. genetic signatures, their geographic and ecological distributions, and species associated with them were Recent outbreaks of emergent zoonotic disease available and stored in accessible databases. Financialunderscore the fact that there is no current international resources should be available for research on reservoircapability to use accessible information about reservoir species and creation of such a database.species to predict future outbreaks or geographic spreador even to identify geographic foci and local prevalence, Infectious disease was the fundamental issueor genetic diversity in most zoonotic viruses. Indeed, in that prompted the creation and drove the developmentmany cases even the species identification and habitat of the state and federal public health agencies andof the natural host reservoir(s) is unknown and impos- regulatory guidelines in the United States. Ironically,sible to determine without field and laboratory research. however, historical success in this realm might haveIn other instances the reservoir species of mammals or bred institutional complacency. Educational trainingbirds have been misidentified based on outdated field programs, research in epidemiology, perceived com-guides or undocumented by voucher specimens stored petency of the American medical profession, effectivein research museum collections, or both (27). Voucher lobbying, and supportive legislation combined to makespecimens are essential to the scientific validity of local and national capabilities appear to be adequate.epidemiological research on zoonotic disease. Such But the occurrence of seemingly ‘new’ diseases in thespecimens of mammals or birds collected in the wild last few decades has altered the political landscape andmust be accessioned into legitimate museum research assumptions about preparedness. For example, thecollections where they can be identified to species. discovery in 1993 of a “new” hantavirus in the UnitedOnce they are stored in such collection facilities, the States (with a fatality rate approaching 50%) led rap-voucher specimens provide a measure of scientific idly to the discovery and geographic localization of ancertainty as to reservoir species identifications because additional 27 strains of the virus in the United Statesthey can be analyzed or double-checked independently. alone (30, 31). The original hantavirus outbreak was wellUncertainty about reservoir species identifications is publicized and captured public attention. Alarm overunfortunate because such information is essential to the outbreak predominated at first. Because many ofunderstanding spatial epidemiology of disease and those who fell ill were Native Americans, there alsooutbreak prediction (28, 29). In particular, once reser- were social implications. Ultimately, questions werevoir species have been identified, it then is practical to raised about public health preparedness. Although theestimate geographical range, habitat requirements, and outbreak of an unknown disease initially had politicalpopulation densities in context of land use and a wide repercussions, the outbreak also led to a substantialrange of other variables. This in turn sets the stage for technical response that included field biology, surveysusing remote sensing—including satellite imagery—to of rodent specimens housed in museum research col-predict outbreaks of zoonotic disease (29). lections, and subsequent laboratory work. On a global scale, governmental ministries and The unexpected appearance of HIV/AIDS isdepartments usually apply the term ‘wildlife’ to natural another incident that altered public perception of infec-disease reservoirs. The alternative, which requires a tious disease. Other emergent diseases such as tick-
  17. 17. Introduction 7borne Lyme disease in the northeastern United States, plinary research on emergent zoonoses with financialthe rapid spread of West Nile virus in birds, livestock, support from federal and state agencies (32, 33). Federaland human beings, and rodent-borne hantavirus-asso- governmental agencies have gradually recognized theciated respiratory disease have attracted attention, but economic, trade, social, and foreign policy significancetheir actual public and economic impacts have been far of unanticipated kinds of human disease. The relation-lower than those associated with HIV/AIDS. ship between emergent diseases and biodefense has significant national security implications. Although this One outcome of the foregoing is that the United relationship is not yet fully appreciated in Washington,States scientific community has focused substantial it has obvious implications for the nonproliferationresearch effort on the ecology of emergent disease. and threat reduction community within the govern-Because this is a complex problem, scientific interest ment. One challenge before us is to discover ways tohas been comprehensive. Zoologists, systematic and integrate the scientific and technological componentsevolutionary biologists, virologists, and ecologists have with United States foreign policy in the field of threatfound ways to work together to conduct multidisci- reduction. An Accidental Confluence of Significant Events Awareness of infectious disease as a national ses, American troops returned from Operation Desertsecurity threat gradually captured attention at the Storm, and, within a few months, an unknown healthhighest levels of the United States Government in the malady dubbed Gulf War Syndrome was reported.1990’s. Today the terrorism of mailed anthrax spores, The ensuing debate seized public and governmentalthe international impact of the SARS outbreak, and attention. Was this a real and previously unknowndire predications about avian influenza H5N1 have arid land disease, a manifestation of psychologicalsolidified the attention of the National Security Council, stress attributable to the threat of chemical or biologi-the White House, and Congress and also have brought cal attack during combat against the Iraqi army, or, inthese issues before the American public. Outbreaks of fact, an actual indicator of Iraq’s use of chemical ornaturally occurring infectious disease are a phenom- biological weapons (CBW)? What was the likelihoodenon that overlaps with biosecurity concerns and has that the troops had encountered a previously unknownpotential linkage to transnational bioterrorism. Collec- disease? No existing database could be mined fortively, these topics merge into a complex mélange that hints about a potential naturally occurring emergenthas significant foreign policy implications. Hopefully, disease or reservoir species distributed in the desertthis is understood in political circles and thus figures along the Persian Gulf. It was not until Novemberprominently in business conducted by the Department 2008 that the United States Veteran’s Administrationof State. issued a report concluding that overuse of pesticides and pyridostigmine bromide, a prophylactic drug that Despite long-time efforts of security and health confers protection from nerve agents, were likelyexperts, it probably was an accidental convergence causative factors (34).of events that contributed most to the increased sig-nificance attached to the subject at the highest level While emergent zoonotic diseases and Gulf Warof government. In addition to the unanticipated ap- Syndrome occupied public attention, another set ofpearance and spread of a dramatic new disease—HIV/ circumstances unfolded independently. First, after theAIDS—with complicated social implications, in the collapse of the Soviet Union in 1991, the capabilityearly 1990’s, West Nile virus unexpectedly appeared of their bioweapons (BW) program gradually becamein major urban centers, hantavirus and Lyme disease known through defectors and other former weaponeersmade news, tuberculosis re-emerged as a global threat, who now were free to talk and write about some of theirand Ebola claimed a deadly toll in Africa. While these experiences. The full scope of this massive programnatural, emergent, zoonotic diseases captured headlines became clear as nonproliferation programs engagedand created health, policy, research, and political cri- dozens of laboratories scattered across the former
  18. 18. 8 Global Disease Surveillance and National SecuritySoviet Union. Second, the United Nations in 1995 In 1996 President Bill Clinton issued a Presi-uncovered and revealed the Iraqi BW program, thus dential Decision Directive that called for a moreconfirming the existence of anthrax and other weap- ‘focused’ United States policy on infectious diseasesonized biological agents and their means of deployment (37). President Clinton also announced $1.4 billon inand delivery (35, 36). By 1997, the potential interplay Federal spending to develop urban response teams,among regional instability, transnational terrorism, and protect government facilities, develop and stockpileprimitive, but frightening, attempts at bioterrorism also vaccines, and enable the nation to detect and diagnosewas increasingly obvious. Most important, all of these outbreaks caused by biological agents.seemingly far-flung subjects shared enough in commonto coalesce under a single heading—infectious disease Collectively, presidential directives and fundingand surveillance—and added up to a significant na- legislation related to disease surveillance had measur-tional security issue. able results. For the first time since early in the Cold War, the public health sector became directly linked The confluence of events had an impact on the to national security. The Department of State listedUnited States government by gradually overcoming the protection of human health and reduction of the spreadinertia associated with its vast bureaucracy. Disease, of infectious disease as national strategic goals. Thehuman and animal health, foreign policy, biosecurity, National Institutes of Health increased funding forand counter-terrorism could no longer be conveniently research on emergent diseases and in early 2000 theparceled to federal agencies and treated as business as National Intelligence Council produced an intelligenceusual. The potential relationship of nonproliferation estimate on the threat of global infectious disease andprograms aimed at redirection of former Soviet weap- its implications for the United States (38). In 2000 andoneers and concerns about natural emergent zoonotic again in 2001, the General Accounting Office (GAO)diseases were noticed at the agencies managing the issued its own reports to Congress on challenges inprograms. Moreover, public health specialists in the improving infectious disease surveillance systems (1,United States and abroad agreed that global disease 39).surveillance systems were inadequate.
  19. 19. Introduction 9 Section Summary • Global disease surveillance is a critically important but complex international issue. • The current system is inadequate for the task on a global scale and in context of national security. • Recent events serve as reminders of lurking infectious diseases and the rapid mutation rates that produce new strains. • Increasing human population size and, therefore, local densities, along with inter- national movement of substantial numbers of people on a daily basis, contribute to evolution of new strains of disease, contagion, and rapid spread. • There is no current capability to use information about reservoir species to pre- dict emergence, spread, foci, prevalence, or genetic diversity in most zoonotic viruses. • Disease, human and animal health, foreign policy, biosecurity, and counter- terrorism cannot be treated as business as usual. • Our knowledge of global pathogens even in the Western Hemisphere is woefully inadequate. • Our ability to forecast disease emergence and spread is technically and math- ematically possible, but lacking.
  20. 20. The 2000 National Intelligence Estimate 11 II. The 2000 National Intelligence Estimate The National Intelligence Estimate (NIE) of 2000 cluded that many of these new diseases would originatereflects the thinking and analysis of the United States overseas. Infectious disease also was seen as a threatGovernment at that time in regard to security issues to U.S. and NATO military operations, especially inraised by infectious diseases (38). Because it was de- developing countries. HIV infection rates were pre-veloped prior to fall 2001, this NIE does not reflect the dicted to increase in Sub-Saharan Africa, in the formeremotional impact and uncertainty following the anthrax Soviet republics (the ‘newly independent states’ ormailings and terrorist attacks on the United States. For NIS), and in unnamed rogue states. Such events werethese reasons, it is an excellent historical starting point predicted to affect military capabilities and recruitmentfor a discussion of where we are and where we should pools. Politically, infectious diseases were predictedbe in terms of global disease surveillance. to have a heavy socioeconomic impact on developing countries (including the NIS), and this impact in turn The NIE for the year 2000 concluded that, “de- would affect the United States through the cost andvelopment of an effective global disease surveillance delivery of humanitarian aid and responses to regionaland response system is probably at least a decade or or local instabilities. Finally, the NIE also highlightedmore away, owing to inadequate coordination and difficulties due to embargos or travel restrictions andfunding at the international level and lack of capac- the interplay between infectious diseases and the po-ity, funds, and commitment in many developing and tential for BW or bioterrorism.former communist states.” The NIE also predictedthat international progress in responding to infectious Three specific aspects of the NIE report meritdiseases would continue to deteriorate for several years retrospective consideration. First, the report focusedbefore measurable progress might occur. This scenario on a short list of human diseases – referred to as thewas deemed the most likely—the alternative scenarios ‘deadly seven’ – given priority based on their mortalitybeing the extremes of steady progress versus stymied rates and significance as assessed by the World Healthprogress—but all three scenarios were over-shadowed Organization (WHO) and the U.S. Armed Forcesby concurrent caveats. All bets were off if a deadly and Medical Intelligence Center (AFMIC). Second, thehighly infectious new disease were to appear, if HIV/ NIE report scarcely accounted for so-called animalAIDS increased catastrophically, or if a contagious bio- diseases that (a) can infect human beings and (b) havelogical agent were to be released by human beings. major economic impact within the United States. Third, the NIE assumed that new diseases would most likely In terms of United States national security, the emerge in developing countries, the Russian Federa-NIE concluded that emerging or re-emerging infec- tion, or in the newly independent states, but not withintious diseases would continue to kill at least 170,000 the United States.Americans annually. Significantly, the NIE also con- The Deadly Seven Diseases Focusing on the deadly seven diseases makes are already devoted to each of the “deadly seven.” Onesense in statistical terms. HIV/AIDS, tuberculosis consequence of such focused support is that interna-(TB), malaria, hepatitis B and hepatitis C, lower respira- tional cooperation on reporting has been achieved andtory infections, various forms of diarrhea, and measles treatment has steadily improved. Given the currentaccounted for the highest number of deaths worldwide resources, response capability, and successes with thein 1998. At the same time, however, each of these dis- deadly seven diseases, is additional surveillance ofeases is well defined, all are diagnosable, and most are these particular diseases required? The answer probablytreatable to some extent. Moreover, massive amounts is no given the cost and other expensive priorities. Butof funding, research, and drug and vaccine development do any of these seven diseases constitute an unusual
  21. 21. 12 Global Disease Surveillance and National Securitythreat to national security? Again the answer is no if lem is that a focus on the “deadly seven” is inadequateone assumes that lesser known or previously unknown and potentially misleading when infectious diseases areinfectious agents constitute a greater threat than well- thought about in context of national security or bioter-known, well-studied diseases. But there might be rorism. Such a focus can lead to an over-commitmentexceptions. One exception is hepatitis, which often is of financial and other resources and a false sense thata co-infective agent, and another possible exception is national security priorities have been satisfied.drug-resistant tuberculosis. Ultimately, the real prob- Animal-borne Diseases Zoonotic (animal-borne) diseases were hardly canalization. The United States is not unique in thismentioned in the NIE report (38). This was an important regard. Animal and human diseases are regarded asoversight that can be explained by the paradigm that different in most countries and this difference extends‘human’ and ‘animal’ diseases are somehow different to the way that governments are organized. Moreover,and biologically unrelated. The historical and cultural there is a widespread homocentric cultural bias: humandivision of medical practice between human beings medicine is typically given priority, regulated to higherand domestic animals is very likely the source of this standards, and provided more financial resources thanartificial categorization. Academically, the division animal medicine, which is relegated as a subset ofbetween animal and human health was reinforced in agricultural issues.the United States by creation of separate human medi-cal and veterinary medical schools and professional In one response to the problem of the animalassociations. It was further reinforced by the fact that versus human disease mentality, the Federation ofin American universities, veterinary medicine is admin- American Scientists created an Animal Health/Emerg-istrated within agriculture and generally restricted to ing Diseases Project (AHEAD) with a focus on devel-Land Grant institutions, which originally usually did oping nations (40). Under this umbrella, the Federationnot have medical schools. Literally, then, the traditional developed the International Lookout for Infectiousveterinary and human medical programs usually do not Animal Diseases (ILIAD)-Tanzania project, which isco-exist on a common campus or even within the same an animal disease surveillance system for deploymentuniversity. They are, in fact, still separate activities in to impoverished rural areas of Africa. The mission ofmost respects. The failure of WHO and OIE to integrate the ILIAD-Tanzania project is to provide “timely andtheir respective surveillance systems was highlighted accurate disease detection, diagnosis, prevention, andin the 2008 report of the Commission on Prevention control” but the rationale is that because many animalof Weapons of Mass Destruction Proliferation and diseases—brucellosis being a good example—can beTerrorism (4). transmitted to human beings, “their management and prevention are crucial to improving public health on a As it grew and matured administratively in the global scale” (40). Another example is the “one world,late 19th Century, the United States federal govern- one health, one medicine” initiative, which aims toment parceled subject matter, policy development, and bridge veterinary and human medicine (www.wcs.orgregulation into different agencies with their own mis- and www.oneworldonehealth.org).sions. Eventually, this led to the U.S. Department ofAgriculture (USDA), the National Institutes of Health It obviously is in the United States’ interest(NIH) and Pubic Health Service (PHS), the Food and for human and veterinary medicine to strive towardDrug Administration (FDA), and the Fish and Wildlife a technically-based coalition. The only cautionaryService (wildlife management and disease control). note is that such a revised relationship between twoToday, historical priority, budget, physical property artificially distanced professions needs to somehowand facilities, congressional authorizations and other include an improved relationship with the biologicalfactors reinforce this administrative and managerial sciences community. While the emphasis here is on
  22. 22. The 2000 National Intelligence Estimate 13medicine, an understanding of emergent disease and working group recommended a strategic approach withzoonoses requires specialized scientifically-based several specific steps.expertise not found in the American medical communi-ties. Mammalogy, medical acarology and entomology, • Create an inter-ministerial committee onand parasitology are examples of academic disciplines zoonotic disease that meets on a regularneeded to provide the expertise required to conduct schedule and is empowered to develop com-comprehensive research and promote preparedness for mon reporting standards and goals.dealing with zoonotic diseases. There also are obviousroles for ecologists, specialists in geospatial analyses • Define stakeholders (e.g., public healthand satellite imagery, and mathematical modelers, just officials, physicians and veterinarians, ag-to point out a few more examples. riculturists, local and regional political and economic interests) and develop respect and The arrival and spread of West Nile Virus in the shared interests.United States illustrates complications that can arisefrom dividing infectious diseases into “animal” and • Develop an inter-ministerial reference labo-“human” illnesses. In this instance, failure to recognize ratory for diagnostics, reporting, and emer-the relationship between bird die-offs and sick human gency response.beings misled the CDC and was one factor that delayedthe correct identification of the infectious agent behind • Create a regional scientific association thatthe epidemic (10). It also was the case that the initial focuses on zoonotic diseaseshuman cases were attributed to St. Louis encephalitisvirus because of geographically-based expectation. • Bring higher education into the process through development of curricula that focus Viewing the world as though ‘animal’ and ‘hu- on biology of disease and ensure that publicman’ diseases are separate biological entities might health integrates the human medical interestsbe more disrupting and limiting for developing na- with veterinarian and agricultural interests.tions than it is for the United States. In the UnitedStates this artificial distinction is mistakenly seen as • When resources are scarce, focus should bemerely a bureaucratic annoyance. But it is imperative on monitoring zoonotic diseases in knownto know that even for the United States this artificial geographic foci rather than the country atworld view has national security implications because large.it has become a paradigm that affects communica-tion, expectation, and ability to think strategically. • When outbreaks occur, WHO and other in-In developing nations it hinders progress, squanders ternational organizations with field responseresources, and misses opportunities for international teams should be quickly invited to assist onfinancial and technical assistance. At a Regional (Kyr- the ground.gyz Republic, Kazakhstan, Uzbekistan, and Tajikistan)Central Asian Disease Surveillance Workshop held in The human- and animal-disease issue is a caseBishkek, Kyrgyz Republic in 2006, one of us (CJP) in which common sense and scientific data must takemoderated a working group on ‘Integrating Human and precedence over political considerations, turf andAnimal Disease Surveillance’ (41). The working group resource issues, and homocentric traditions. Approxi-included scientists, health specialists, representatives mately 75% of diseases that have emerged over the lastfrom WHO, FAO, U.S. Naval Medical Research Unit-3 30 years have been zoonotic (animal-borne) diseases(NAMRU-3), and governmental representatives from that are transmitted to human beings. Moreover, ~60%the Kyrgyz Republic, Tajikistan, the United States, of all infectious diseases typically associated withCanada, and the UK. The private business sector humans actually are shared with other mammal spe-was represented by Black & Veatch, a company that cies. None of this is surprising from the perspective ofhas developed software for disease surveillance. The evolutionary biology. Although evolution primarily is
  23. 23. 14 Global Disease Surveillance and National Securityregarded as an academic subject, evolutionary theory One can easily gain a sense of this by exploring theactually has broad applicability (42). In this instance, economic impact of natural outbreaks. The rapidlyphylogenetic analyses result in ‘trees’ that illustrate evolving virus associated with blue-ear disease (por-historical relationships and these trees are the starting cine reproductive and respiratory syndrome—PRRS)point for understanding the biological distributions of in southeastern China and Viet Nam is a case-in-point.infectious agents. This swine disease has affected international relation- ships and led to a 1% decline in China’s GDP (46). Additional, new, emerging zoonotic diseases ofconcern will inevitably have wild animal reservoirs. With the foregoing in mind, any program forDevelopment of research teams with combined exper- global disease surveillance must integrate all of thetise (human health, veterinary medicine, and biology) resources and information about disease withoutwould be a valuable strategy for dealing with this chal- regard to the unnecessary and artificial separation oflenge (43, 44, 45). Zoonotic diseases can be adapted to use diseases into ‘animal’ and ‘human’ disease. The termas biological (and economic) weapons. For the United ‘species-neutral’ has been applied to the idea of suchStates, a successful bioterrorist attack on the agricul- integration, which must be a priority when it comes totural sector could have dire economic consequences. United States national security. The Role of Emergent Disease According to the NIE Emergent zoonotic diseases constituted the single timeline to provide adequate opportunity to prevent sig-major assumption in the NIE, which anticipated that nificant impact on humans, nations, and economies.developing countries would be the likely sources ofpreviously unknown infectious agents. Emergent dis- The United States presumably is better studiedease represents the unknown, and experience to date geographically, and potential reservoir species forwith HIV/AIDS, Ebola, Marburg, and Nipah encepha- emergent zoonotic diseases are better known, than is thelitis, hantavirus and arenaviruses in North and South case with most other politically defined regions of theAmerica, a wide variety of Asian hemorrhagic fevers, world. But even in the United States we know very littleand SARS is not encouraging (39, 47, 48). In most of these about how infectious diseases are transmitted directlyexamples, reservoir species—the species of animal in or indirectly to people from wild reservoir species. Notwhich the virus resides over long time periods and the only have 27 new hantavirus strains been discoveredgeographic limits of distribution of these “reservoir” since 1993, but two additional hantaviruses pathogenicspecies—are either unknown or imperfectly known (27). to humans have been discovered just in New MexicoIn most cases, environmental factors and mode(s) of since that time (30). On a global scale, zoonotic diseasestransmission also are scientific mysteries. The same generally are associated only with domestic livestockthings can be said about potential vectors, which usually or ‘wildlife’ rather than with particular species of wildare the insects or ticks and chiggers (or both) that can mammals or birds. There are several reasons why thistransmit disease agents from a host reservoir species to is the case, beginning with a lack of voucher specimensanother animal, including human beings. To a variable that specialists can use to identify species. Globally,degree these emergent diseases are being “managed” it also is the case that local specialists are scarce andwithin reasonable statistical limits. But because of an outbreak response is in the hands of agencies that areabsence or paucity of data and analyses, the next new strictly associated with either public (human) health oroutbreak cannot be predicted geographically or epide- agriculture and veterinary medicine.miologically. Even though scientists think they haveidentified the chimpanzee reservoir of HIV-1 virus and It is important to know that technically it isthat with phylogeographic analysis have developed a feasible to detect, isolate, and genetically characterizerobust hypothesis for the origin of HIV/AIDS, it still previously unknown infectious agents. Both SARS intook 25 years to make that discovery. Given the rate at Asia and hantavirus-associated pulmonary syndromewhich new diseases emerge, 25 years is far too long a in the United States are good examples of successful
  24. 24. The 2000 National Intelligence Estimate 15technical response to unexpected outbreaks. At the available in nature. Based on the experience in thesame time, it also is true that in both examples the out- United States, the known infectious agents probablybreaks document how political priorities can complicate represent only a fraction of those that are available inthe process of responding to a new disease (31, 49). But natural reservoirs. The compelling question is: couldregardless of the political challenges, it is possible to a disease surveillance system be developed to recog-determine the geographic patterns of viral circulation, nize potentially dangerous but still emergent zoonoticgenetic diversity and virulence, prevalence of an agent diseases, and, if so, how could it be done?in natural populations, and identifications of reservoirspecies and vectors. Moreover, the scientific expertise Although the NIE focused on specific importantalso is available to identify and genotype reservoir spe- but well-known diseases, the report included a brief sec-cies (such as mammals and birds) and vectors (such as tion on ‘Economic Development and Land Use,’ whichectoparasites or mosquitoes) and to predict ecological addressed factors that influence emergent disease. Theor climatological factors influencing emergent disease. NIE drew the following conclusions (38).Although U.S. government agencies and the scientificcommunity are engaged in these kinds of projects, • Changes in land and water use patterns willthere is no centralized program to systematically ac- remain major factors in the spread of infec-quire and integrate the information into databases that tious disease.can be interactively interrogated in the United States.Integrating these efforts and being able to model the • The occurrence of Lyme disease in theimpact of global climate change on reservoir species, United States and Europe has been linked totheir evolution, their geographic and ecological distri- reforestation.bution, and their migration or other movements will bea critical requirement in coming decades (50). • Conversion of grassland to farm land in Asia encourages growth of rodent populations Emergent zoonotic diseases are an extreme con- carrying hemorrhagic fever and other viraltrast to some common non-infectious human diseases diseases.such as hypertension and most cancers. In the lattercase, many human beings succumb every year and there • Human encroachment on tropical forests willis a massive technological response. In the former case, bring populations into closer proximity withrelatively fewer people die, but the disease constitutes insects and animals carrying diseases.a greater public health threat because (a) the mortal-ity rate in new outbreaks can be high, (b) very little is • Close contact between humans and animalsknown about their epidemiology, (c) we have no ability in the context of farming will increase theto predict the emergence of a new variety, and (d) the incidence of zoonotic diseases.national security risk includes the need for redirectionand rapid response and the possibility of terrorism or • Water management and agricultural irrigationsome other international complication. In comparison will encourage spread of water-breeding vec-to hypertension or cancers or most of the “deadly seven” tors such as mosquitoes and snails that havediseases, only emergent pathogens have special national contributed to outbreaks of Rift Valley feversecurity implications. There is a realistic potential for and schistosomiasis in Africa.them to be harvested or acquired during legitimate re-search projects and from there be used in bioterrorism Technical and scientific issues can be raised withor state-sponsored biological weapons (BW) programs all of these sweeping generalizations but it is neverthe-(51, 52). The potential for intentional release of a previ- less noteworthy that the NIE recognized the threat ofously unknown but naturally occurring infectious agent emergent diseases and concluded that environmentalshould be a matter of concern. Acquisition of such a factors and human activities were important consid-novel agent does not require sophisticated laboratory erations.manipulation, and such novel agents will always be
  25. 25. 16 Global Disease Surveillance and National Security Section Summary • The National Intelligence Estimate (NIE) concluded that emerging or re-emerging infectious diseases would kill at least 170,000 Americans annually. • The NIE assumed that new diseases would most likely emerge in developing countries, the Russian Federation, or in the newly independent states. • Animal diseases are hardly mentioned by the NIE, which is an important over- sight. • A program for global disease surveillance must integrate all resources and infor- mation and should be a priority for United States national security. • Emergent diseases constitute a significant threat because (a) very little is known about their epidemiology, (b) we have no ability to predict the emergence of a new variety, (c) these infectious agents frequently are deadly when contracted by human beings, and (d) these agents are potential resources for transnational bioterrorists. • Since 1973 at least 30 deadly new diseases have been identified on a global scale. • The NIE recognized the threat of emergent diseases and concluded that environ- mental factors and human activities were important considerations. • Global climate change will have a profound impact on reservoir species.
  26. 26. Global Disease Surveillance: Problems and Concerns 17 III. Global Disease Surveillance: Problems and Concerns The National Intelligence Estimate (NIE) of 2000 of resources (especially through the WHO), earlyand General Accounting Office (GAO) reports to Con- warning of influenza strains, geographic spread of thegress in 2001 identified several specific challenges to deadly seven, re-emergence of old diseases (dengue,global disease surveillance (38, 39). In 2008, the Com- measles, polio, and drug-resistant TB being examples),mission on Prevention of Weapons of Mass Destruction and notification of new, emergent, diseases. If the in-Proliferation and Terrorism concluded that: ternational goal is to access this array of information, the current patchwork assembly does a modest job of Disease surveillance and reporting remains a accomplishing the goal. But at the same time, there difficult and demanding task…and outbreak are evident weaknesses and problems (53). The most information is not always provided by WHO obvious problems are driven by political or economic member states on a timely basis. Today’s factors and can be conveniently organized as a set of international surveillance networks are not questions: comprehensive in their coverage…[and] reporting delays may result from political or • How reliable and available are laboratory and bureaucratic hurdles as well as the lengthy chemical diagnostics, especially in develop- laboratory analyses needed to confirm a dis- ing countries? ease diagnosis (4). • Under what political, economic, or social Although there are many challenges to the sys- circumstances are data withheld?tem, to a large extent previously identified problemswere focused on the differences between developed and • What diseases are of greatest public signifi-developing countries, with the conclusion that emer- cance, how are they diagnosed or recognized,gent diseases are most likely to appear in developing and how does this vary across countries orcountries (38). Rather than begin by focusing on the regions?developmental status of different countries, we preferto first establish the goals and priorities of global dis- • If emergent diseases first appear in rural orease surveillance and then identify the problems and remote regions (especially in technologi-challenges. cally underdeveloped nations), what is the likelihood of their detection or recognition, Presently, the term “disease surveillance”— or both?defined by us as the ability to detect, identify, and moni-tor the occurrence of disease on a broad geographic • Should information gathering be coupledscale—is widely used but typically is treated as if it to international response and health carerepresents a single unified international goal. In fact, delivery?the Centers for Disease Control (CDC) in the UnitedStates and the World Health Organization (WHO) and • Is it misleading or misguided to focus onnumerous other ministries and agencies in various certain diseases—such as the deadly seven—nations constitute a patchwork of resources that more common to human beings and virtuallyor less monitor disease occurrence in human beings. ignore animal diseases?The central international theme, if there is one, is in-formation gathering. The secondary theme, especially • Does “syndromic surveillance,” which isrecently, is response. based on pre-diagnoses data, offer advan- tages? Information gathering is used for such things asstatistical summaries, analysis of trends, allocation
  27. 27. 18 Global Disease Surveillance and National Security Diagnostics Medical diagnostics traditionally was an ‘art.’ In countries that are overwhelmed by healthEventually, however, laboratory-based diagnostics care challenges, precise diagnostics take a back seatbecame feasible, rapid, and widely available, especially to direct treatment of symptoms. In post-war Iraq, forin the United States, Canada, and Western Europe. This example, years of poor sanitation, pooled runoff, andtechnical advance gradually supplanted the largely lack of potable water in the typical home is consistent(but not totally) subjective artistry of physicians. In with widespread diarrhea that takes a high toll on chil-countries where laboratory diagnostics became rou- dren. From a practical perspective, precise diagnosis oftine, the use of laboratories contributed heavily to the bacterial or viral agents is possibly less important thanincreased cost of health care. In the United States this medical care directed at symptoms. From a resourcecost increase was largely offset by economic strength perspective, significant improvements in infrastructureand health insurance, two factors that do not apply to and public awareness might be immediately moremost of the world. Diagnostic costs have continued important than sophisticated diagnostics. In terms ofto increase as new technologies—such as real time recent history and culture, the Iraqis—including theirPCR—have become available, making access to the scientific community—frequently express the thoughttools increasingly difficult for developing countries. that cancers are on the increase. Quite sensibly, they point to environmental contamination as the likely Routine diagnostic capabilities in the United source. In Iraq, however, there are no reliable data onStates have developed to the point that precise infor- the geospatial distribution of cancers prior to the firstmation is available and diseases and causes of mor- Gulf War, in most cases there are no local, regional,tality can be regarded as reasonably reliable as long or national records that are accessible, and accurateas well-characterized diseases are involved. Data of diagnostics, especially in areas outside of Baghdad,similar reliability can be obtained from Europe, Canada, probably do not exist.Australia, and Japan, but not from most of the rest ofthe world. In many places, diagnostics are simplified In any country where political intention su-or improvised. The result is a lack of standardization persedes factual information, trustworthy diagnosticof diagnostics, which increases statistical uncertainty data, or acceptable statistical analysis, it is essentiallyand makes accurate analyses of data and trends very impossible to conduct any type of disease surveil-difficult. The idea of routine laboratory assays is not lance. Also, under such circumstances the nationan option either because laboratories in many countries suffers because governmental decision-making re-are unavailable, or ill equipped. Other factors also garding scarce financial and human resources will beare at play. For instance, routine laboratory-based affected. In Iraq, where infectious disease is a majordiagnostics often are impractical because of cost or challenge, the new (post-Saddam) government has hadbecause the laboratories are operated by technicians to address propaganda about depleted uranium aheadwithout equivalent levels of training as counterparts in of infectious disease. Although no medical recordsmore developed countries. Moreover, when it comes or disease surveillance reports exist, the propagandato human beings, economic reality and historical and assertion was made that “elevated rates of cancers,cultural differences also inevitably intrude on any at- congenital abnormalities, genetic defects, infertility,tempt at standardization in diagnostics. renal and hepatic dysfunction, cardiovascular diseases, malnutrition, spread of infectious disease, and death Veterinary diagnostics exhibit a similar inter- have all occurred” as a result of depleted uranium,national pattern of variability in quality. Economic electromagnetic fields, and “unusual oxygen ions” infactors probably have the greatest impact, especially the atmosphere (54). After several years of distraction,in developing countries where health ministries are independent assessments of depleted uranium by theoften funded at a higher level than their agricultural World Health Organization (55) and United Nationscounterparts. The historical divide between “human” Environmental Programme (UNEP) (56) did not sup-and “animal” diseases probably exacerbates the chal- port the claims.lenge in developing countries.
  28. 28. Global Disease Surveillance: Problems and Concerns 19 The foregoing paragraphs argue that reaction to decision-making, and dissipate scarce resources. Allrecent history, culturally determined response to situ- of these inter-related factors can affect the capabilityation, a local sense of priority, international politics, of obtaining trustworthy diagnostic data to support anyand the struggle for resources can interact in ways type of internationally standardized disease surveil-that confuse priorities, diminish the role of science in lance system. Information Gathering A global disease surveillance system presumes Ironically, however, it is possible that some countries,that countries will willingly share health information especially some of the former Soviet republics, willfrom within their borders. However, it is important to share disease information with the United States orappreciate that this frequently is not the case. A clas- the EU or even the Russian Federation more readilysic example is the East African refusal in the 1980’s to than with neighboring states. Information sharing isadmit the dramatic impact of HIV/AIDS. Economic a complex problem in which critically important datafactors such as tourism, trade, and investment along might reach a central database before being exchangedwith cultural and political expediencies interact to make between neighboring states. One might predict thatit unlikely that nations will continue to share informa- regardless of the causes, impediments to data sharingtion in the absence of treaties or other binding legalities. will hamper local decision-making and response. Emergent Disease, Reservoirs, Vectors, and Geographic Hotspots It is important to know that new, emergent quickly spread across the United States, is associatedzoonotic disease is not just a phenomenon of develop- with wild bird species, especially crows (59).ing countries. In the United States Lyme disease isvector-borne, transmitted by a species of tick. Lyme In China, an unanticipated outbreak of the deadlydisease was first recognized in Connecticut, not far SARS virus in late 2002 was first detected in Guang-from New York City, and now either has spread or dong Province, but not reported. By March 2003, thehas been diagnosed for the first time across much of disease had spread to the United States and Europethe nation (57). Species of small rodents in the genus and by April confirmed cases were reported from IndiaMicrotus (often called voles) are the usual reservoir and Africa. Epidemiologists traced SARS to marketsof this disease. Arenaviruses are another example. and concluded that the virus occurred in palm civets,Although arenavirus infections in human beings were which were brought to village markets and thus createdwell-known from South America, it was unknown in a pool of potentially infected animals in contact withthe United States. Indeed, the first human cases in the large numbers of people. In 2005 it was discoveredUnited States were diagnosed in California within the that a species of horseshoe bat (genus Rhinolophus) islast decade. In this instance a species of woodrat (ge- the natural SARS reservoir (60). If bats are the naturalnus Neotoma) is the most likely reservoir. Yet another reservoirs, palm civets probably are accidental hosts.example is hantavirus-associated pulmonary syndrome.This disease was first recorded in New Mexico, but In Patagonian Argentina a unique strain of han-Black Creek Canal virus (a strain of hantavirus associ- tavirus (Andes virus) was transported to human beingsated with a species of cotton rat, Sigmodon) infected from a species of wild rice rat (genus Oligoryzomys),people in Dade County Florida, and the Sin Nombre and the outbreak seriously affected the economy of thestrain of the virus carried by deer mice (Peromyscus) ski resort city of Bariloche, where it was first detected.has infected people in more than 20 states and several Unlike the cases of hantavirus in the United States, aCanadian provinces (31, 58). A final example is West subset of the Argentine cases possibly resulted fromNile virus. This virus, which arrived recently and then person to person transmission (61).
  29. 29. 20 Global Disease Surveillance and National Security Examples of emergent zoonotic disease are found most likely to be sources of emergent diseases, how willthroughout Latin America, Africa, northern Europe, cases be recognized? Who could identify a new diseaseAustralia, and Asia. Although it might be the case that in the absence of suitable diagnostics for an unknowninfections are most likely to occur in remote or rural infectious agent, or the absence of diagnostic capabilityareas where human beings come into contact with wild to eliminate alternative, previously known, pathogens?animal reservoirs, good data on incidence are scanty. It is unrealistic to think in terms of sentinel stations inIt is likely that the first deaths from such events occur remote or rural areas on a global scale, and with the lackfairly commonly in remote areas where medical care of diagnostic capability the challenge is reduced veryis essentially non-existent or, if it exists, there is no little by restricting sentinel stations to select developingroutine reporting or diagnostic capability and no epi- nations. On the other hand, these are the circumstancesdemiological or public health services. The local or under which the syndromic surveillance system mightregional scientific infrastructure often is ill-equipped be well-suited to detect an outbreak of disease.to respond to outbreaks or to genetically characterizenew agents or conduct other relevant research. One Several aspects of emergent zoonotic diseaseexception to this was seen in Southeast Asia where must be considered in order to develop a strategy fortalented local (Malaysian) scientists teamed with in- disease surveillance that includes previously knownternational collaborators to respond to an outbreak of or future unknown emergent diseases. Although ahuman encephalitis and identify a new virus (Nipah) research track record exists, the fact is that essentialresponsible for the disease (62, 63). More typically, such information about reservoir species—such as theira response is impossible. Even with good infrastructure identity (and ability to identify them), geographicalit is possible for an emergent zoonotic disease to be distribution, ecology, and historical relationships to thea surprise. In the United States, hantavirus was first infectious agents that they harbor—is unknown withdiagnosed in 1993, and although 27 additional strains few exceptions. The best available comprehensive datahave been characterized since then, undiagnosed deaths come from North America and Western Europe, wheresurely occurred at some unknown rate in the thousands it is more convenient to conduct the necessary fieldof years that humans in the American Southwest have studies. Vast areas of Asia, Africa, and South America,shared living space with deer mice prior to 1993. all of which are significant to understanding emergent zoonoses, are essentially unknown. Factors such as global climate change, habitatdegradation, human population density and distribu- A far better understanding of infectious agentstion, and landscape conversion to agriculture (or from and their complicated biological relationship with theiragriculture back to a feral status) are logical contribu- hosts is needed. Problems exist in understanding thetors to increased contacts among human beings, reser- instances in which vectors are involved in the trans-voir species of mammals, and vectors (64, 65, 66). But mission of disease from the reservoir animal to humanadditional scientific data are still needed to establish beings. Ectoparasitic vectors—such as fleas, ticks, andrelationships and develop predictive models with rea- chiggers—are incompletely known, taxonomically.sonable statistical value (29). Such research is underway Undescribed species are involved in transmission ofin a variety of laboratories that approach the problem infectious agents, especially in remote regions, andfrom multiple perspectives—environmental degrada- taxonomists with the expertise to identify them aretion, remote sensing, molecular biology, field biology becoming scarce throughout the world’s scientific com-and reservoir natural history, and systematic biology. munity. Reservoir and vector species identification isIn reality, however, one of the major challenges is that a critical and powerful piece of information. Whenthe mechanisms and factors that facilitate interspecies placed in a geospatial database, such data can be usedtransfers by pathogenic viruses are unknown. to predict the distribution of pathogenic viruses in context of land use, regional climate and local weather Given the complexities involved, how can any patterns, ecology, and human population densities andglobal disease surveillance system account for emer- movements. Moreover, such information can lead togent diseases? If the NIE is correct, and remote or even outbreak prediction.rural areas of developing countries are indeed the places

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