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Quarantine Stations at Ports of Entry: Protecting the Public’s Health 1 Introduction To mitigate the risks posed by microbial threats of public health significance originating abroad, the Centers for Disease Control and Prevention (CDC) places small groups of staff at major U.S. airports. These staff, their offices, and their patient isolation rooms constitute quarantine stations, which are run by CDC’s Division of Global Migration and Quarantine (DGMQ). Positioned at major national gateways, the CDC quarantine stations have experienced first-hand the impact of globalization on public health. The rapid speed and tremendous volume of international and transcontinental travel, commerce, and human migration enable microbial threats to disperse worldwide in 24 hours—less time than the incubation period of most diseases. These and other forces intrinsic to modern technology and ways of life favor the emergence of new diseases and the reemergence or increased severity of known diseases. Meanwhile, the risk of bioterrorism has become a pressing national security issue. Taken together, these factors have stimulated calls for greater vigilance for microbial threats of public health significance at U.S. gateways. Some of those calls have focused attention on the number and role of CDC quarantine stations at U.S. ports of entry. Congress began to allocate funds in fiscal 2003 for the establishment of new quarantine stations at 17 major U.S. ports of entry that comprise airports, seaports, and land-border crossings. In a significant departure from the recent past, both the preexisting 8 quarantine stations and the new 17 are expected to play an active, anticipatory role in nationwide
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Quarantine Stations at Ports of Entry: Protecting the Public’s Health BOX 1.1 Statement of Task Conduct an assessment of the role of the federal quarantine stations given the changes in the global environment, including large increases in international travel, threats posed by bioterrorism and emerging infections, and the movement of animals and cargo. The quarantine stations played a new and important role in the SARS response in 2003. The recognition of their contributions has resulted in increased funding to expand the number and scope of the stations. The assessment is needed to guide the expansion. Issues to be considered include: The current role of quarantine stations as a public health intervention and how the roles should evolve to meet the needs of the 21st century. The role of other agencies and organizations working collaboratively with the CDC’s Division of Global Migration and Quarantine at ports of entry (including federal partners such as Customs and Border Protection, Immigration and Customs Enforcement, U.S. Department of Agriculture, and U.S. Fish and Wildlife Service). The role of state and local health departments as partners for public health interventions at the nation’s borders (such as activities focused on emergency preparedness and response, disease surveillance, and medical assessment and follow-up of newly arriving immigrants and refugees). Optimal locations for the quarantine stations for efficient and sufficient monitoring and response. Appropriate types of health professionals and necessary skill sets to staff a modern quarantine station. Surge capacity to respond to public health emergencies. biosurveillance (DHS, 2004; Gerberding, 2005). Consequently, DGMQ asked the Institute of Medicine (IOM) to convene an expert committee to assess the present CDC quarantine stations and recommend how they should evolve to meet the challenges posed by microbial threats at the nation’s gateways.1 DGMQ specifically requested “an assessment of the role of the federal quarantine stations, given the changes in the global environment including large increases in international travel, threats posed by bioterrorism and emerging infections, and the movement of animals and cargo” (Box 1.1). To conduct this assessment and provide recommendations, IOM convened, in October 2004, the Committee on Measures to Enhance the Effectiveness of the CDC Quarantine Station Expansion Plan for U.S. Ports of Entry. The committee’s expertise comprises clinical infectious disease, epi- 1 Contract No. 200-2000-00629, Task Order No. 31.
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Quarantine Stations at Ports of Entry: Protecting the Public’s Health TABLE 1.1 Locations, Jurisdictions, and Staffing of CDC Quarantine Stations at U.S. Ports of Entry (Established and Nascent), May 2005 and October 2005 Forecast Location of Quarantine Station Jurisdiction No. of Full-Time Equivalents May 2005 Oct. 2005 (forecast) Anchorage N/A 1 2 Atlanta* (Hartsfield International Airport) All ports in Georgia, Alabama, Arkansas, Louisiana, Oklahoma, Mississippi, North Carolina, South Carolina, and Tennessee 3 4 Chicago* (O’Hare International Airport) All ports in Illinois, Indiana, Iowa, Kansas, Kentucky, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin; preclearance port in Torontoa 3 6 Dulles, VAb (Washington Dulles International Airport) N/A 1 3 El Paso, TX (Land border crossing) N/A 2 3 Honolulu* (Honolulu International Airport) All ports in Hawaii, Guam, and Pacific Trust Territories 3 4 Houston (Houston Intercontinental Airport) N/A 2 3 Los Angeles* (Tom Bradley International Airport) All ports in Southern California, Arizona, Colorado, Las Vegas, Nevada, New Mexico, Texas, and the U.S.–Mexico border 4 6
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Quarantine Stations at Ports of Entry: Protecting the Public’s Health Miami* (Miami International Airport) All ports in Florida, Puerto Rico, and the U.S. Virgin Islands 6 7 Minneapolis N/A 1 2 Newark N/A 1 2 New York City* (John F. Kennedy International Airport) All ports in New York, Connecticut, Delaware, District of Columbia, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, Pennsylvania, Rhode Island, Vermont, Virginia, and West Virginia; preclearance ports in Montreal and in Dublin and Shannon, Ireland 7 8 San Diego (Land border crossing) N/A 1 4 San Francisco* (San Francisco International Airport) All ports in Northern California, Nevada (except Las Vegas), Utah, and Wyoming 4 6 San Juan N/A 1 2 Seattle* (Seattle-Tacoma International Airport) All ports in Washington, Alaska, Idaho, Montana, and Oregon; preclearance ports in Edmonton, Calgary, Vancouver, and Victoria, Canada 4 4 TOTAL: 44 66 NOTE: N/A = information not yet available; jurisdictions for all stations will be redefined once new stations are fully staffed or nearly so. *Established station (as of May 2005). aPreclearance port: A foreign port where individuals who are traveling to the United States undergo—in theory—the same visual screening and other disease surveillance activities conducted at U.S. ports of entry by CDC quarantine station staff. bDulles, VA, is located approximately 26 miles from Washington, D.C. SOURCES: DGMQ, 2003; personal communication, M. Remis, DGMQ, May 11, 2005.
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Quarantine Stations at Ports of Entry: Protecting the Public’s Health demiology, U.S. public health practice, international public health practice, community health education and nursing, and public health law. In addition, three consultants to the committee provided insights into the surveillance, detection, and management of disease in animals and animal products being imported into the United States, CDC quarantine station activities in relation to U.S. seaports, and international laws and regulations relevant to the expansion plans for the CDC quarantine stations. At the sponsor’s request, the committee released the interim letter report Human Resources at U.S. Ports of Entry to Protect the Public’s Health in January 2005 to provide preliminary suggestions for the priority functions of a modern quarantine station, the competences necessary to carry out those functions, and the types of health professionals who have the requisite competences (Appendix A). This, the committee’s final report, assesses the present role of the CDC quarantine stations and articulates a vision of their future role as a public health intervention. STUDY METHODS The committee gathered information for this report from journal articles, reports, and news articles; presentations and commentary by constituencies relevant to the study (Appendix B); facts provided by the sponsor at the committee’s request; visits by select committee and staff members to five quarantine stations; congressional testimony; and the commissioned papers contained in Appendixes D–F. These information-gathering activities took place between October 2004 and June 2005. CDC Quarantine Stations: What They Are, What They Do Quarantine stations have served as a public health intervention at U.S. gateways since the nation’s infancy; much has been written about their historic role. Where and how do these stations function today? Although there are quarantine stations both inside the United States and at its borders, this report deals exclusively with those stations located at ports where people, goods, and conveyances from international points of origin may enter this country. The United States has 474 ports of entry2 (CRS, 2004); CDC quarantine stations were established at eight of them as of May 2005 (Table 1.1). Figure 1.1 illustrates the present relationship 2 This report uses the term “port of entry” to mean any air, land, or sea port through which people, cargo, and conveyances may legally enter the United States from abroad. It should be noted that “port of entry” has a slightly different meaning when used by the Department of Homeland Security’s U.S. Customs and Border Protection (CBP). In CBP’s case, a Port of Entry is an administrative center whose jurisdiction may include more than one entry facility
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Quarantine Stations at Ports of Entry: Protecting the Public’s Health FIGURE 1.1 The relationships among the members of the Quarantine Core (shaded boxes, boldface type) and their partner organizations in the Department of Health and Human Services (white boxes, boldface type). Nonpartner agencies, centers, and divisions within DHHS are also noted in the diagram (white boxes, italicized type). NOTE: CDC = Centers for Disease Control and Prevention; DHHS = Department of Health and Human Services; DGMQ = Division of Global Migration and Quarantine; FDA = Food and Drug Administration; NCID = National Center for Infectious Diseases; NIH = National Institutes of Health. SOURCES: CDC, 2005; Cetron, 2004. in a certain geographic area. For instance, the Philadephia Port of Entry services Philadephia International Airport, Philadelphia’s seaport, Trenton Mercer Airport, Atlantic City International Airport, and ports in Lehigh Valley, PA (http://www.cbp.gov/xp/cgov/toolbox/contacts/ports/pa/1101.xml). Thus, the United States has fewer CBP Ports of Entry (312) than literal ports of entry (474).
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Quarantine Stations at Ports of Entry: Protecting the Public’s Health among the CDC quarantine stations, DGMQ and its branches, CDC, and other federal agencies. Unlike physical areas that travelers pass through, the term “station” in this report refers to a group of one to eight individuals located at an airport, land crossing, or seaport who perform activities designed to help mitigate the risk that microbial and other threats of public health significance may enter the United States or affect travelers to this country. As noted above, all of the established stations (as of May 2005) are located at airports. Although the staff have offices and one or more patient isolation rooms, most interactions between quarantine station staff and travelers or crew take place in public areas of the terminals. Microbial Threats of Public Health Significance Microbes in the context of this report are bacteria, viruses, protozoa, fungi, and prions that can replicate in humans. A microbial threat of public health significance causes serious or lethal human disease and is transmissible from person to person, from animal to person, or potentially both; it also may be transmissible from food or water to people. Because of their potential for wide dispersal, concern is greatest for microbes that spread rapidly from person to person. A microbial threat may be introduced intentionally—as in bioterrorism—or unintentionally. Additional threats of public health significance of concern to the quarantine stations include the release of chemical or radiological substances and of biological substances other than microbes (e.g., microbial toxins). Overview of Authorities and Activities Legal Authorities The quarantine station staff have the delegated authority to detain, medically examine, or conditionally release individuals at U.S. ports of entry who are reasonably believed to be carrying a communicable disease of public health significance. The federal authority vested in DGMQ to order the medical evaluation of such individuals can supersede the public health powers of states and localities under specific circumstances. In addition, DGMQ and CDC can set policies to prevent certain animals that pose a public health threat from entering the country. Chapter 3 contains a more thorough discussion of these legal and regulatory powers, their applications, and their limitations.
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Quarantine Stations at Ports of Entry: Protecting the Public’s Health Modern Uses of Quarantine and Isolation The staff of a CDC quarantine station conducts many activities, including ensuring the quarantine of specific individuals and animals. Quarantine is the separation and restriction of movement of apparently healthy persons or animals that may have been exposed to a microbial threat and therefore may become infectious (DGMQ, 2004a). On a related note, a CDC quarantine station may also ensure the isolation of specific individuals or animals infected by a specific microbial threat. Through isolation, the infected persons or animals are separated from the population at large, and their movement is restricted to prevent the microbial threat from spreading (DGMQ, 2004a). Quarantine and isolation at national borders are important nonmedical components of the public health toolkit for limiting and containing the spread of microbial threats. Their effectiveness varies, however, depending on the nature of the threat and the extent to which it has spread. Summary of Primary Activities Today, the CDC quarantine station staff at U.S. ports of entry primarily perform the following activities (Committee, 2005;3 Appendixes D and E): Reviewing shipping manifests to identify cargo that may pose a public health threat; ensuring that the shipment is inspected by a quarantine inspector or, more frequently, an inspector from a partner federal agency; and ensuring that identified threats are contained. Obtaining and reviewing the results of immigrants’ overseas medical examinations, identifying immigrants who have Class A or B diseases (Box 1.2), and mailing those results to the state and local health departments with jurisdiction at the immigrants’ final destinations. Meeting arriving refugees and parolees, visually screening them for signs and symptoms of illness, reviewing the results of their overseas medical examinations, giving local health departments notification of their arrival and the results of their overseas examinations, and alerting the health departments to arrivals with Class A or B conditions. Responding to calls from port-based inspectors from other federal agencies about cargo that may pose a public health threat. 3 As already noted in this chapter, committee members visited five quarantine stations over the course of the study. This series of site visits, which included meetings with DGMQ field staff as well as federal and local partners, served as a major means of data collecting for the committee and as an evidence base in writing the report. The citation “Committee, 2005,” which appears throughout the report, refers to the committee’s notes from these visits. The notes are available in the study’s public access file.
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Quarantine Stations at Ports of Entry: Protecting the Public’s Health BOX 1.2 Class A and Class B Conditions In the context of medical examinations of individuals who seek refuge in the United States or want to immigrate to this country: Class A conditions generally render an alien ineligible for entry into the United States; they include Communicable diseases of public health significance, including chancroid, gonorrhea, granuloma inguinale, human immunodeficiency virus (HIV) infection, leprosy (infectious), lymphogranuloma venereum, syphilis (infectious stage), and tuberculosis (active). A physical or mental disorder and behavior associated with the disorder that may pose, or has posed, a threat to the property, safety, or welfare of the alien or others. A history of such a disorder and behavior that is likely to recur or lead to other harmful behavior. Drug abuse or addiction. In certain cases, a waiver may be issued to an individual with a Class A condition for entry into the United States. When this occurs, immediate medical follow-up is required. Class B conditions comprise a “physical or mental abnormality, disease or disability serious in degree or permanent in nature amounting to a substantial departure from normal well-being” (Medical Examination of Aliens. 42 C.F.R. §34.4 ). Individuals with Class B conditions may enter the United States, but must receive medical follow-up soon after arrival. SOURCES: Medical Examination of Aliens. 42 C.F.R. §34.1–34.8 (2004); Massachusetts Department of Public Health, 2000. Visually screening passengers of airplanes arriving from foreign points of origin for signs or symptoms consistent with a quarantinable disease (Box 1.3). Responding to ill passengers (international travelers, immigrants, and refugees) and crew reported by pilots, ship masters, and others. Developing and maintaining relationships with local public health authorities and other System partners at ports within the station’s jurisdiction. Overseeing the importation of nonhuman primates to assure that the process is performed according to a protocol designed to prevent the transmission of zoonotic disease to humans if the nonhuman primates were infected.
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Quarantine Stations at Ports of Entry: Protecting the Public’s Health BOX 1.3 Quarantinable Communicable Diseases By executive order of the president of the United States, federal isolation and quarantine are authorized for the following communicable diseases: Cholera. Diphtheria. Infectious tuberculosis. Plague. Smallpox. Yellow fever. Viral hemorrhagic fevers (Lassa, Marburg, Ebola, Crimean-Congo, South American, and others not yet isolated or named). Severe acute respiratory syndrome (SARS). Influenza caused by novel or reemergent influenza viruses that are causing, or have the potential to cause, a pandemic. SOURCES: Executive Order 13,295 of April 4, 2003: Revised List of Quarantinable Communicable Diseases. Code of Federal Regulations, title 3 (2003); Executive Order 13,375 of April 1, 2005: Amendment to Executive Order 13, 295 Relating to Certain Influenza Viruses and Quarantinable Communicable Diseases. Code of Federal Regulations, title 3 (2005). Inspecting plants and animals that may pose a public health threat and are imported by passengers. While the staff of all the established stations perform these primary functions, each station’s particular priorities are determined by its geographic location, the number of full-time staff and their capabilities, and a range of other factors. Chapter 3 elaborates upon all of these activities in detail. FRAMING THE ISSUE As the aviation industry learned from the outbreak of severe acute respiratory syndrome (SARS), the CDC quarantine stations are uniquely positioned to coordinate nationwide responses to global microbial threats of public health significance that have the potential to reach—or cross—U.S. gateways (Meenan, 2005; personal communication, K. Andrus, Air Transport Association, October 21, 2004). Such responses are unusually complex because they often involve multiple organizations that cross sectors, jurisdictions, and nations. As this report will make clear, CDC quarantine stations have the capability in some cases and the potential in others
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Quarantine Stations at Ports of Entry: Protecting the Public’s Health to orchestrate and facilitate these organizationally complex public health responses. Therein lies the stations’ chief value to the U.S. population and travelers to this country. The CDC Quarantine Stations: A National Insurance Policy In addition to performing the array of daily activities listed above, the CDC quarantine stations serve as part of the United States’ national insurance policy against public health catastrophes. As is the case with personal insurance, one hopes never to need it, but if a catastrophe occurs, one is relieved the insurance is there. Such public health emergencies as the global outbreak of SARS exemplify “low-likelihood, high-consequence events”—a term used in such industries as insurance and emergency management to describe events that are infrequent or have a low probability of occurring but have potentially catastrophic consequences if and when they occur. Uncertainty surrounds low-likelihood, high-consequence events; a cost-benefit assessment is unclear. Efforts to prepare for such events, which may occur years or decades in the future, may be criticized in the present (IOM, 2005). Strengths and Limitations of Isolation and Quarantine at National Borders Strengths Quarantine and isolation at national borders are traditional nonmedical components of the public health toolkit for limiting and containing the spread of microbial threats. The effectiveness of these traditional functional capabilities varies, however, depending on the nature of the threat and the extent to which it has spread. In a recent assessment of the threat of pandemic influenza, the World Health Organization (WHO) concluded that nonmedical interventions, including the health screening of travelers, “can potentially reduce opportunities at the start of a pandemic and slow international spread” (WHO, 2005, p. 52). Such interventions will be the principal protective tools pending the production and distribution of vaccine supplies, the report found. The presence of trained public health officials at U.S. ports of entry also can have a powerful psychological benefit, particularly for the thousands of port-based workers. The knowledge that a member of the CDC quarantine station staff will board a plane that has reported a case of serious communicable disease and will manage the situation might give port workers the confidence to come to work even during serious outbreaks of disease (Committee, 2005). The confidence-building value of such activities as those
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Quarantine Stations at Ports of Entry: Protecting the Public’s Health performed by the CDC quarantine stations has also been recognized by WHO. Although the health benefit of screening travelers coming from areas affected by serious communicable disease remains unproved, WHO recommends that it be permitted (but not encouraged) before and during an influenza pandemic “for political reasons, to promote public confidence” (WHO, 2005, p. 60). Limitations Many of the CDC quarantine stations’ present activities focus on the detection of disease in persons, animals, cargo, and conveyances during the window of time shortly before and during arrival at U.S. gateways. Yet the pace of global trade and travel has narrowed that window dramatically. Consequently, infected individuals and animals do not necessarily develop signs of disease while in transit or by the time of arrival, and available noninvasive diagnostics cannot always identify infected travelers with reasonable sensitivity, specificity, and speed. Thus, the quarantine stations can identify only a small percentage of infected people and animals. It is instructive to note that the index case of SARS in Toronto would not have been detected by border quarantine officials had they existed at the time,4 because that individual was presymptomatic when she returned to Canada from Hong Kong (Personal communication, R. St. John, Public Health Agency of Canada, July 5, 2005). Microbes incubate undetected in their healthy hosts—whether human, animal, or insect—for widely varied lengths of time before the host exhibits signs of infection. Usually, clinical tests are required to detect infections during the presymptomatic period of disease. Yet there are known diseases for which modern medicine has no clinical diagnostic tools for the presymptomatic state. Moreover, today’s diagnostic tools may not recognize novel and dangerous infections in their preclinical state or could lead to misdiagnoses, as happened during the first several months of the SARS outbreak in China (IOM, 2004). The use of clinical diagnostic tools in general to detect infection in affected travelers takes more time than the present air travel system allows. One quarantine inspector reported he had approximately 30 seconds to determine whether an international traveler displays any signs or symptoms of an infectious disease of public health significance (Committee, 2005; personal communication, R. St. John, Public Health Agency of Canada, 4 The quarantine system that exists today at Canadian ports of entry was created in response to the SARS outbreak.
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Quarantine Stations at Ports of Entry: Protecting the Public’s Health July 5, 2005). A sea change in social attitudes toward commerce and privacy, as well as an enormous federal investment in public health infrastructure and human resources, would be necessary for presymptomatic tests to become realistic options in the United States. Refugees and individuals outside the United States applying for an immigrant visa are required to undergo x-ray and diagnostic tests for specific communicable diseases of public health concern before they may receive a U.S. visa and leave their country of origin (DGMQ, 2004b). With the exception of these individuals, however, the Quarantine Network could rarely detect infection in presymptomatic humans and animals entering the United States, even under ideal circumstances. STRUCTURE OF THIS REPORT Chapter 2 orients the reader to the recent history of quarantine stations at U.S. ports of entry and to the details of the expansion plan. Chapter 3 contains a description of the committee’s findings about the present CDC quarantine stations, including their capacities, methods, operating environment, and linkages. In Chapter 4, the committee presents its conclusions and recommendations on how the quarantine stations should evolve to meet the challenges posed by microbial threats at the nation’s gateways. REFERENCES CDC (Centers for Disease Control and Prevention, Department of Health and Human Services). 2005. New CDC Structure. [Online] Available: http://www.cdc.gov/maso/pdf/CDCOperationalStructure.pdf [accessed June 9, 2005]. Cetron M. 2004. CDC Division of Global Migration and Quarantine. Presentation at the October 21, 2004 Meeting of the IOM Committee on Measures to Enhance the Effectiveness of the CDC Quarantine Station Expansion Plan for U.S. Ports of Entry, Washington, DC. Committee (IOM Committee on Measures to Enhance the Effectiveness of the CDC Quarantine Station Expansion Plan for U.S. Ports of Entry). 2005. Unpublished. Notes on Site Visits to DGMQ Quarantine Stations. CRS (Congressional Research Service, The Library of Congress). 2004. Border Security: Inspection Practices, Policies, and Issues. [Online] Available: http://fpc.state.gov/documents/organization/33856.pdf [accessed April 7, 2005]. DGMQ (Division of Global Migration and Quarantine, National Center for Infectious Diseases, Centers for Disease Control and Prevention). 2003. Quarantine Stations. [Online] Available: http://www.cdc.gov/ncidod/dq/quarantine_stations.htm [accessed September 20, 2004]. DGMQ. 2004a. Fact Sheet: Isolation and Quarantine. [Online] Available: http://www.cdc.gov/ncidod/dq/sars_facts/isolationquarantine.pdf [accessed May 6, 2005]. DGMQ. 2004b. Medical Examinations. [Online] Available: http://www.cdc.gov/ncidod/dq/health.htm [accessed January 26, 2005].
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Quarantine Stations at Ports of Entry: Protecting the Public’s Health DHS (U.S. Department of Homeland Security). 2004. Bio-Surveillance program initiative remarks by Secretary of Homeland Security Tom Ridge and Secretary of Health and Human Services Secretary Tommy Thompson. [Online] Available: http://www.dhs.gov/dhspublic/display?theme=43&content=3093 [accessed October 4, 2004]. Gerberding J, Director, Centers for Disease Control and Prevention. 2005. A Hearing on the Centers for Disease Control and Prevention. Statement at the Apr. 6, 2005 hearing of the Subcommittee on Labor, Health and Human Services, Education and Related Agencies, Committee on House Appropriations, U.S. House of Representatives. IOM (Institute of Medicine). 2004. Learning From SARS: Preparing for the Next Disease Outbreak. Knobler S, Mahmoud A, Lemon S, Mack A, Sivitz L, Oberholtzer K, Editors. Washington, DC: The National Academies Press. IOM. 2005. The Smallpox Vaccination Program: Public Health in an Age of Terrorism. Washington, DC: The National Academies Press. Meenan JM, Executive Vice President and Chief Operating Officer, Air Transport Association of America Inc. 2005. Statement of John M. Meenan. Statement at the Apr. 6, 2005 hearing of the Subcommittee on Aviation, Committee on Transportation and Infrastructure, U.S. House of Representatives. WHO (World Health Organization). 2005. Avian Influenza: Assessing the Pandemic Threat. Geneva: World Health Organization.
Representative terms from entire chapter: