the State and Local Response to Bioterrorism
Ann I. Winters
Joel Ackelsberg
Marcelle Layton
Marc Paladini
Debra Berg
Sara T. Beatrice
BACKGROUND
After the anthrax terrorist events of 2001, there was recognition at local, state, and federal levels of the importance of improving and maintaining the public health infrastructure as a primary defense against bioterrorism. In January 2002, the Department of Health and Human Services announced the availability of $1.1 billion in federal funding that would be made available to all states and four large urban areas (Chicago, District of Columbia, Los Angeles, and New York City) in federal fiscal year 2003 to address critical gaps in bioterrorism public health preparedness and response plans and infrastructure.
Federal funding for biodefense increased over the next several years through FY2006, trended down through FY2008, and has increased modestly in recent years. The FY2010 federal budget for biodefense totaled $6.05 billion (1), with a significant portion applied to programs that serve multiple public health goals in addition to improving bioterrorism preparedness, according to an “all hazards” approach to disaster preparedness.
At the local and state levels, public health preparedness continues to develop on many fronts, creating expanded capacities for rapid and effective responses to incidents caused by intentional (e.g., bioterrorism) or accidental releases of biological threat agents (BTAs). Local and state health authorities must be able to recognize the occurrence of unusual disease manifestations, clustering, or increases in infectious disease illnesses through a variety of surveillance systems. Detection must be followed by prompt epidemiologic, environmental, and laboratory investigation, and an intentional source must be distinguished from a natural cause.
Once a BTA event is suspected, public health authorities need to be able to mobilize rapidly to identify the time, location, and method (e.g., aerosol vs. foodborne) of the release and conduct ongoing surveillance and epidemiologic investigations to characterize the extent of the outbreak. Local and state public health departments must be closely coordinated with the appropriate governmental agencies at the local and state (e.g., emergency management, police, emergency medical services), regional (neighboring state and county authorities, especially public health counterparts), and federal (e.g., Departments of Health and Human Services, Homeland Security, Defense, and Justice) levels. This coordination relies heavily on preexisting relationships and agreements with these agencies.
Local and state health authorities must also be able to communicate with and assist healthcare providers in the community through routine, well-established mechanisms. Linkages with the local healthcare provider, hospital, longterm care, home care, and laboratory communities are essential for successful engagement during a crisis. Public health authorities must determine whether antibiotic or vaccine prophylaxis is indicated and, if so, must be prepared to coordinate with emergency management agencies and the healthcare community to provide medications to potentially exposed persons.
In addition to effective communication with the provider community, local and state public health authorities must be prepared to communicate effectively with and engage the public at every step in the BTA investigation, even when information is limited.
By enhancing their capacities required for rapid and effective responses to outbreaks caused by potential BTAs, public health agencies are better prepared when naturally occurring public health emergencies occur (Table 102-1). This was evident in the local, state, and federal responses to the challenges of the 2009 H1N1 pandemic.
STATE AND LOCAL HEALTH DEPARTMENTS IN THE UNITED STATES
Public health authority in the United States resides mostly at the state and local levels, with the powers of our federal public health agencies being limited and specific to certain key areas (e.g., international and interstate quarantine, and regulation of drugs and vaccines). At the state level, the public health role focuses on ensuring that statutory authority is in place for both routine and emergency health activities, monitoring statewide disease surveillance in coordination with local health units, developing policy and guidelines for disease control activities, providing reference laboratory services, and supporting local public health agencies through financial or technical assistance. In contrast, local public health activities focus more directly on the collection of disease surveillance data; case and
contact management activities to control disease spread (e.g., provision of immune globulin for hepatitis A contacts or directly observed therapy for tuberculosis); and, in some localities, direct provision of healthcare (2). However, great heterogeneity exists with respect to personnel capacity, services offered, and organizational structure among state and local health departments in the United States. In some states, public health is decentralized, with most activities and services occurring at the local level, and with state officials providing more of an oversight and advisory role. In other states, there are no local health units, and all public health activities are conducted by the state. An even greater diversity of capacity and services exists among local health departments. In some large urban areas, the local health agencies are larger than many state health departments and function independently, whereas in more rural counties, resources may be quite limited with minimal professionally trained staff, thus requiring a greater reliance on state-level support.
contact management activities to control disease spread (e.g., provision of immune globulin for hepatitis A contacts or directly observed therapy for tuberculosis); and, in some localities, direct provision of healthcare (2). However, great heterogeneity exists with respect to personnel capacity, services offered, and organizational structure among state and local health departments in the United States. In some states, public health is decentralized, with most activities and services occurring at the local level, and with state officials providing more of an oversight and advisory role. In other states, there are no local health units, and all public health activities are conducted by the state. An even greater diversity of capacity and services exists among local health departments. In some large urban areas, the local health agencies are larger than many state health departments and function independently, whereas in more rural counties, resources may be quite limited with minimal professionally trained staff, thus requiring a greater reliance on state-level support.
TABLE 102-1 BTA Preparedness Checklist for Local and State Public Health Agencies | |||
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ROUTINE LINKAGES BETWEEN PUBLIC HEALTH AND THE HEALTHCARE SECTOR
Public health authorities routinely interface with the healthcare sector on many levels. One of the core missions of public health agencies is the control of communicable diseases. This legal mandate requires the close coordination between public health officials and their local healthcare provider, hospital, and laboratory communities. Traditionally, disease surveillance activities depend on prompt reporting by healthcare providers and laboratorians concerning suspect or confirmed cases of notifiable diseases to local and state health departments.
One of the most important linkages at the local level is between public health officials, infection preventionists (IPs), and healthcare epidemiologists. IPs and healthcare epidemiologists serve as the primary points of contact in hospitals for surveillance and disease control activities during both community- and healthcare-associated outbreaks and serve a critical role in any hospital’s ability to respond to a BTA event. Case investigations by public health officials often require communication with the reporting clinician or hospital IPs, whether for more detailed clinical and/or epidemiologic data or to help facilitate the collection, packaging, and transport of appropriate clinical specimens for testing at public health reference laboratories (e.g., rabies or botulism).
In addition to reliance on IPs and healthcare epidemiologists for surveillance and case investigation, public health officials routinely request assistance from the provider community when postexposure prophylaxis is indicated for contacts at risk of potential secondary transmission (e.g., hepatitis A or invasive meningococcal disease).
Partnerships between health departments and the medical provider community are also essential in implementation of public health prevention campaigns. Examples of this successful partnership include the response to the epidemic of multidrug-resistant tuberculosis in the early 1990s (3); perinatal hepatitis B prevention programs; HIV counseling, testing, and partner notification programs; and vaccination campaigns for seasonal influenza and high-risk groups for hepatitis A (4).
BIOTERRORISM PREPAREDNESS REQUIRES ENHANCED LINKAGES
Bioterrorism preparedness requires building on linkages between the public health, hospital and medical care sectors that are already in place to confront routine public health problems. The terrorist events of 2001 highlighted gaps in the capacity of the healthcare system to respond to large-scale health events. In 2002, the Congress created the Hospital Preparedness Program in the U.S. Department of Health and Human Services. One of the significant outcomes of this program has been the development of healthcare coalitions (5) composed of healthcare facilities and response agencies (including and often led by local and state public health authorities).
Healthcare coalitions work together regionally to create comprehensive response plans tailored to the specific capacities and needs of the local communities. Hospital preparedness programs and healthcare coalitions enable the local medical and public health communities to become familiar with each other before a public health emergency occurs. Recent examples of linkages between public health authorities and the healthcare community include enlisting primary care clinic staff to deliver vaccinations or prophylactic antibiotics, training emergency medicine physicians and nurses to recognize and initiate treatment of BTA-related diseases, and partnering with intensivists to plan for surge capacity in critical care. Additionally, providers from pediatrics, obstetrics, and geriatrics were targeted to increase vaccination among their high-risk patients during the recent 2009 H1N1 pandemic.
Medical providers and key hospital staff (e.g., infection preventionist and microbiology staff) should know the local and state health departments’ 24-hour, 7-day-a-week emergency contact numbers and Web site information and should be registered for public health electronic communication systems (e.g., Health Alert Network, broadcast facsimile, and e-mail health alert systems such as the Centers for Disease Control and Prevention’s (CDC’s) Clinician Outreach and Community Activity Listserv at http://www.bt.cdc.gov/coca) that provide urgent notification of the community during acute events.
Key aspects of plans that need to be in place for the public health response to suspected or confirmed incidents involving BTAs parallel what should be used for naturally occurring infectious disease outbreaks. The 2009 H1N1 pandemic was a naturally occurring outbreak that demonstrated the need for many of these capacities and highlighted some of the ongoing challenges for public health emergency preparedness planners (6).
INTERAGENCY AND INTERSECTOR COORDINATION AND COMMUNICATION
Just as established linkages between public health authorities and the healthcare sector must be enhanced before an emergency occurs, strong relationships must be in place between public health agencies and other relevant local, state (e.g., emergency management, police, emergency medical services, fire/hazmat, and poison control centers), and federal (e.g., CDC and Federal Bureau of Investigation [FBI]) agencies prior to a public health emergency, whether a BTA event or a natural outbreak. A centralized emergency operations center is essential to facilitate intraand interjurisdictional coordination and communication. In the event of an emergency, predesignated representatives from all involved agencies and any local or state hospital associations should be assigned to this center to ensure effective coordination of the overall response.
The public health sector’s communication, transportation, and other equipment or infrastructure needs for disaster response should be assessed prior to an emergency. Essential resources include reliable and redundant communication capacity (e.g., cellular telephones, handheld devices [with e-mail/Internet access], laptop computers with modem, twoway and 800-MHz radios, and satellite telephones); broadcast facsimile and e-mail capability; secure Internet sites (e.g., Health Alert Network) to rapidly notify and inform the healthcare sector regarding events of public health concern; and computer systems that are networked between the local and state health department, the local emergency management command center, and appropriate state and federal agencies. Additionally, hospitals and some primary care clinics have enhanced their own redundant communication systems to improve and ensure internal and external communication with employees, public health authorities, and first responder agencies. Backup generators should be available not only in healthcare settings but also for use by public health authorities, as demonstrated by the 2003 blackout in New York City when a delay in obtaining generators limited the public health response (7). Finally, an alternative location for emergency operations personnel to meet must be identified, in the event that the primary emergency operations center is damaged or otherwise unavailable.
If personnel are expected to use specific equipment and procedures during an emergency, they must be trained and demonstrate proficiency beforehand. To the extent possible, these response measures should be based on routine operations. It is unreasonable to expect unfamiliar plans, protocols, procedures, or equipment to be implemented or used effectively during an emergency.
While training for public health staff should include the clinical, laboratory, and epidemiologic features of disease caused by exposure to potential BTAs, it should also focus on the expected roles and responsibilities of agency staff during response activities. Key challenges facing public health officials once a BTA incident is detected include characterizing the scale and scope of the biological hazard; estimating accurately and rapidly those populations at risk from exposure to the biological hazard; distributing effective countermeasures efficiently and within a time frame that will prevent infection among those exposed; supporting the healthcare system that will be treating potentially thousands of casualties; and disseminating accurate and frequent guidance and updates for the public and providers. Importantly, these activities must be performed within an incident management structure that is consistent with national standards.
Effective training tools include tabletop and field exercises, with involvement of representatives from all key local, state, and federal agencies and representatives from the local medical and laboratory communities. These exercises provide the opportunity to test assumptions in existing plans and work out issues related to decision-making authority and respective roles and responsibilities among the disciplines that would be involved in responding to a BTA event. A successful exercise includes a written after action report that highlights gaps in preparedness that should be addressed through follow-up meetings and revision of written plans, if indicated, and reevaluated with periodic exercises.
DETECTION OF A BTA EVENT: TRADITIONAL AND NONTRADITIONAL SURVEILLANCE SYSTEMS
If there were a delay in detecting an outbreak caused by a BTA release, public health preventive interventions might be less effective than if started sooner, and the impacts on morbidity and mortality could be substantial (8). The
diseases caused by potential BTAs may not be suspected or diagnosed rapidly for a number of reasons: initial presentations may be nonspecific (e.g., influenza-like prodrome of anthrax); most physicians in the United States have little or no clinical experience with the diseases caused by these agents (e.g., anthrax, tularemia, botulism, or smallpox); laboratory diagnosis may require days or longer for presumptive identification (e.g., tularemia); the epidemiology and clinical presentation of diseases caused by intentional dissemination may differ from what is found in naturally occurring disease; and more common microorganisms could be used that might not be associated immediately with criminal intent (e.g., enteric pathogens).
diseases caused by potential BTAs may not be suspected or diagnosed rapidly for a number of reasons: initial presentations may be nonspecific (e.g., influenza-like prodrome of anthrax); most physicians in the United States have little or no clinical experience with the diseases caused by these agents (e.g., anthrax, tularemia, botulism, or smallpox); laboratory diagnosis may require days or longer for presumptive identification (e.g., tularemia); the epidemiology and clinical presentation of diseases caused by intentional dissemination may differ from what is found in naturally occurring disease; and more common microorganisms could be used that might not be associated immediately with criminal intent (e.g., enteric pathogens).
State and local public health officials should consider the different surveillance strategies for detection of BTA-related incidents and need to be alert to potential ways in which they could present. A potential BTA dissemination should be considered by public health authorities or healthcare professionals if any of the following occurred:
A single suspected or confirmed case of an illness resulting from exposure to a potential BTA occurring in a patient without a plausible explanation for his or her illness (e.g., a case of plague in the absence of a recent travel history to a recognized endemic area).
Multiple patients presenting with a similar clinical syndrome that has unusual characteristics (e.g., unusual age distribution or previously healthy individuals), is clustered by time and/or space (e.g., all became symptomatic within the same approximate time period or attended the same special event), or involves unusually severe illness, without an obvious etiology or explanation.
An unexplained and marked increase in the incidence or severity of a common syndrome above seasonally expected levels (e.g., a sudden increase in influenza-like illness especially if during the summer and if rapid diagnostic tests were negative for influenza and other common respiratory viruses).
If a potential BTA incident is suspected, an investigation should be initiated immediately to determine the etiologic agent and the likely source of infection, including whether or not a natural route of transmission exists. Because the above circumstances could result from intentional, accidental, or natural exposures, it is important for those evaluating and managing routine cases and/or outbreaks to keep an open mind to all possibilities. Investigations of what appeared to be routine foodborne outbreaks, upon further epidemiologic and laboratory investigation were found to have resulted from intentional contamination of food with enteric pathogens (9,10). In contrast, when diseases associated with exposure to a potential BTA occur in a nonendemic area, intentional dissemination (e.g., bioterrorism) could be a possibility; however, a natural explanation also must be considered. In 2002 in New York City, two bubonic plague cases occurred in residents of New Mexico who were exposed to plague bacilli shortly before traveling to New York (11). Inhalation, cutaneous, and gastrointestinal anthrax also have occurred in recent years following exposure to contaminated animal hides and African (12,13 and 14).
There are a number of surveillance methodologies used for detecting BTA incidents that focus on recognizing or detecting (a) a suspected or confirmed case or illness cluster resulting from exposure to a potential BTA; (b) communitywide or localized increases in influenza-like illness activity or other nonspecific syndromes or increases in potential markers of early prodromal illness (e.g., over-the-counter drug sales); (c) an increase in unexplained, severe infectious illnesses or deaths; or (d) nucleic acid from select bacteria or viruses in air samples collected routinely by environmental biomonitoring programs.
Traditional Public Health Surveillance
Traditional public health surveillance for BTA-associated illness relies on enhancing the medical and laboratory communities’ familiarity with these agents, with the goal of improved reporting of suspected or confirmed illnesses potentially caused by a BTA, as well as reporting of unusual disease manifestations or illness clusters. Most local and state health codes require that physicians, hospitals, and laboratories report a defined list of notifiable infectious diseases. Many state public health agencies have added all CDC Category A and most Category B agents that were not already included on their reportable disease lists (15). In addition, recognizing the need to detect newly emergent diseases that are not yet listed on the health code, most states also require reporting of any unusual disease clusters or manifestations.
Early recognition of a BTA-associated event depends in large part on astute clinicians and laboratorians recognizing one of the index cases based on a suspicious clinical, radiologic, or laboratory presentation (e.g., a febrile illness associated with chest discomfort and a widened mediastinum on chest radiograph in an otherwise healthy adult suggests inhalation anthrax). Isolated cases presenting at separate hospitals will not be recognized as a potential outbreak unless they are reported promptly to the local health department, where the population-based aberrations in disease trends are more likely to be noticed. Previous examples of astute clinicians recognizing and reporting unusual disease clusters or manifestations that led to the detection of a more widespread outbreak includes an outbreak of hantavirus in the southwestern United States (16), Legionnaires disease associated with the whirlpool on a cruise ship (17), an outbreak of Cyclospora associated with contaminated raspberries imported from Guatemala (18), and the initial outbreak of West Nile virus in New York City in 1999 (19). Similarly, the initial detection of anthrax in 2001 was due to a physician who recognized that large gram-positive rods in a patient’s cerebrospinal fluid could be Bacillus anthracis (20). By reporting this suspected case of meningeal anthrax, rapid confirmation was facilitated in a state public health reference laboratory. Weeks later, a suspected case of inhalation anthrax was recognized and promptly reported to and confirmed by public health authorities in New York City (21).
To inform clinicians and laboratorians regarding their essential role in recognizing and reporting suspected or confirmed illness caused by exposure to potential BTAs, public health officials need to promote the importance of disease reporting through ongoing educational efforts. Targeted outreach efforts should focus on specialists in key areas, such as infectious diseases, infection control, microbiology, emergency medicine, dermatology, and neurology. Educational
outreach should emphasize the clinical presentations and diagnostic clues for specific BTA-associated illnesses (e.g., anthrax, plague, and smallpox) and unusual illness patterns suggestive of an intentional outbreak. One lesson learned during the 2001 anthrax outbreak was that public health and medical professionals need to keep in mind all potential clinical manifestations caused by BTA exposure. Cutaneous anthrax—not inhalational disease—was the sentinel illness in New York City. Educational materials also should emphasize prompt reporting of any unusual disease clusters or manifestations to the local or state health department as paramount to the early recognition of natural, intentional, and accidental outbreaks caused by BTA releases. Educational outreach is also needed for key members of the local first responder community (e.g., hazmat, police, and emergency medical services).
outreach should emphasize the clinical presentations and diagnostic clues for specific BTA-associated illnesses (e.g., anthrax, plague, and smallpox) and unusual illness patterns suggestive of an intentional outbreak. One lesson learned during the 2001 anthrax outbreak was that public health and medical professionals need to keep in mind all potential clinical manifestations caused by BTA exposure. Cutaneous anthrax—not inhalational disease—was the sentinel illness in New York City. Educational materials also should emphasize prompt reporting of any unusual disease clusters or manifestations to the local or state health department as paramount to the early recognition of natural, intentional, and accidental outbreaks caused by BTA releases. Educational outreach is also needed for key members of the local first responder community (e.g., hazmat, police, and emergency medical services).
The following methods can be used to help increase awareness of BTA-associated illnesses in the medical and laboratory communities:
Oral presentations targeting specialists in internal medicine, emergency medicine, pediatrics, dermatology, neurology, family practice, infectious diseases, geriatrics, pathology, laboratory medicine, intensive care, pulmonary, radiology, and primary care physicians; physicians-in-training and medical students; medical examiners; veterinarians; and microbiologists.
Public health bulletins (22), newsletters, posters, or pocket cards that present overviews of the clinical aspects of infections caused by potential BTAs (e.g., clinical presentation, laboratory diagnosis, treatment, and prophylaxis) and emphasize the importance of promptly reporting any unusual disease clusters or manifestations to the local and state health departments. These educational materials should be updated and redistributed periodically to maintain ongoing awareness of and sensitivity to these issues.
Posting educational materials on the health department’s public Web site with links to other useful resources (23), including the CDC (http://www.cdc.gov), the Infectious Disease Society of American (http://www. idsociety.org), the American Society for Microbiology (ASM; http://www.asm.org), and the Center for Infectious Disease Research and Policy at the University of Minnesota (http://www.cidrap.umn.edu).
Development of teaching slides and videos that can be distributed to academic and community-based physicians (train-the-trainer modules). Because many health departments may not have sufficient staff with the expertise or time to meet every request for a talk on the clinical aspects of the BTA and the threat of bioterrorism, efforts should be made to provide teaching materials (e.g., slide presentations with speaker notes) to interested local colleagues in infectious diseases, infection control, or other specialties to do presentations to medical staff at their own institutions or organizations.
Improving the overall relationship between the health department and the medical community is an important element that makes it more likely that providers will report promptly. Efforts to improve provider relations and streamline physician reporting should be prioritized. Web-based and other electronic methods can be offered for routine case reporting. During emergencies, a consistent telephone number could be used for provider hotlines (e.g., 1-800-MDREPORT). This would facilitate efficient and timely triage of provider and laboratory calls to clinically trained health department personnel. Dissemination of surveillance data routinely and during emergencies also can foster the ongoing, collaborative relationship between public health and the medical and laboratory communities. These efforts have the additional benefit of improving all aspects of local public health surveillance.
Outbreaks of West Nile virus (24) and monkeypox (25) underscored how public health departments could benefit from establishing and maintaining active collaborations with the animal health community. Many potential BTAs cause zoonotic disease (e.g., anthrax, plague, and tularemia), and animal populations might be affected in unpredictable ways.
Historically, with the exception of rabies-related issues, local and state infectious diseases epidemiologists have not had strong relationships with clinical veterinarians and wildlife specialists in their community. However, with the continued emergence of new zoonotic disease threats, including those related to bioterrorism, local, state, and federal public health agencies have taken steps to improve communication between these communities. Veterinarians have been hired within communicable disease programs to foster collaboration. Requirements have been expanded to include reporting by animal health specialists of suspected or confirmed illness in an animal that might be caused by a potential BTA (26). Similar to the list of notifiable diseases in humans, these regulations also can require reporting of any unusual disease clusters or manifestations in animals.
Nontraditional Surveillance Systems (Syndromic Surveillance)
In the event of an unknown, intentional, or accidental BTA dissemination with the potential to cause thousands of casualties, rapid detection and characterization of the outbreak would be crucial. The swift mobilization of surveillance and epidemiologic resources to determine the place, time, extent, and method of the release would help target preventive measures, speed the epidemiologic and criminal investigation, and reduce public anxiety. For diseases with short incubation periods such as inhalation anthrax, the window of opportunity to respond and to reduce morbidity and mortality is narrow. Therefore, surveillance systems that rapidly provide information on the potential magnitude and geographic scope of a BTA incident, that is, “situational awareness,” are paramount.
The traditional public health surveillance system, based on passive reporting of a limited number of defined, notifiable diseases, may not be sufficient for early detection of a large accidental BTA release or for early recognition of the extent of its impact. Some diseases caused by these pathogens (e.g., tularemia) have nonspecific and protean clinical presentations, and laboratory diagnosis may be time-consuming. Thus, alternative systems that allow prompt recognition of unusual disease manifestations, clusters of illness, increases above expected seasonal levels of common syndromes (e.g., influenza-like illnesses), or deaths resulting from unknown infectious causes are potentially useful components of bioterrorism surveillance.
Surveillance for nonspecific clinical syndromes using data available in existing electronic health databases is considered a potentially valuable adjunct system for the timely detection of illness caused by exposure to a BTA. Although many of the most concerning potential infections (e.g., anthrax, plague, smallpox, and viral hemorrhagic fever) have distinct clinical characteristics once the disease is fully manifest, initial symptoms include a nonspecific febrile prodrome similar to influenza-like illness. Large numbers of botulism cases, on the other hand, would present with symptoms pointing to autonomic and voluntary motor nerve dysfunction. Nonspecific gastrointestinal symptoms would predominate if a food item was contaminated with an enteric pathogen.
Because many medical providers and laboratorians in the United States have limited experience with these pathogens, diagnosis may be delayed. Therefore, the first indication that large-scale exposure to a potential BTA has taken place might be an increase in nonspecific symptoms at the community level. Surveillance for these increases in nonspecific syndromes (e.g., respiratory, gastrointestinal, or neurologic) constitutes the cornerstone of syndromic surveillance used for emergency response purposes (27).
The ideal features of a syndromic surveillance system for early detection of a BTA-related outbreak include the ability to detect changes in disease trends that are based on health event information available continuously, in close to real time or at least in 12- to 24-hour increments. Health event information is most timely when it is electronic, gathered routinely for other purposes, and not limited by diagnostic or recording delays. Syndromic surveillance systems based on clinical data have proven most popular, but other sources such as over-the-counter drug sales may also have utility.
Electronic data that may provide a reflection of community-wide illness are increasingly available, including emergency department visit logs (28), ambulance dispatches (29), ambulatory care encounters (30), data from electronic health records (31), and sales of prescription and over-the-counter pharmaceuticals (32). The most reliable electronic data sources are those that already exist (e.g., emergency department and outpatient visits) and that do not rely on additional collection or reporting of data by medical providers. In many systems, these data include geographic information (e.g., home or work zip code or location of store), theoretically enabling the detection of localized disease outbreaks and monitoring of the geographical extent at a given point in time of a potentially widespread event.
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