- Email: [email protected]
Terrorism from a Public Health Perspective
Terrorism from a Public Health Perspective R. GREGORY EVANS, PHD, MPH; JAMES M. CRUTCHER, MD, MPH; BROOKE SHADEL, PHD, MPH; BRUCE CLEMENTS, MPH; MICHAEL S. BRONZE, MD
ABSTRACT: The use of biological and chemical weapons as agents of warfare and terrorism has occurred sporadically, but recent events demonstrate the increasing risk and possibility that terrorist groups with grievances against the government or groups may employ them. Historically, most evaluations of the potential risk for biological weaponry have focused on the military, but the recent release of anthrax in the United States demonstrates that civilian populations are also at risk. More likely than not, most bioterrorism events will be of a small scale; however,
agents such as Bacillus anthracis and Yersinia pestis could leave hundreds of thousands dead or incapacitated. The impact of the attack will depend on a number of variables, including the agent used, method of dispersal, and the responsiveness of the public health system. With any large-scale event, the public health infrastructure will be called upon to deal with mass casualties and the “worried well.” KEY INDEXING TERMS: Bioterrorism; Public health; Emerging infections; Bioweapons. [Am J Med Sci 2002;323(6):291–298.]
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(BT) events. We do not have the command structure, the training, or the resources necessary for the task. Yet we are making advances in preparedness at the local level. Each day that passes since September 11 brings municipalities closer to having plans to deal with terrorism. Some of these advances will be discussed later in this article. Although first responders will be on the front lines of a terrorist attack that might employ conventional bombs, radiation, and chemicals, in a biological attack, they will play only a secondary role. In a BT attack, the people on the front lines will be the practicing physicians who will diagnose and treat diseases and public health epidemiologists and laboratory personnel who will determine who has been exposed. They will decide who should be treated and how, and they will provide the mechanism to rapidly disseminate this treatment. Furthermore, in the case of transmittable diseases, it is the public health epidemiologists who will determine who must be quarantined to prevent the spread of the disease. However, public health systems in the United States have received far less federal money to prepare for acts of terrorism than have traditional first responders. In fact, in most parts of the United States, local public health and medical care professionals have inadequate training and resources to respond to a major terrorist attack, whether conventional or biological. The 12 hours immediately after the detection of a BT attack are crucial for saving lives and minimizing public panic. Antibiotics and vaccines must be provided immediately to thousands of people potentially exposed to an airborne release of deadly bacteria or viruses. Law enforcement agencies and the National Guard must be told which quarantine mea-
n September 11, 2001, police, firefighters, and emergency medical technicians rushed to the scene of devastation at the World Trade Center. Their quick response and specialized training helped save thousands of lives, contained damage, and provided reassurance that a command and control structure was firmly in place. For more than 2 months, the country was terrorized by cases of anthrax originating from 3 contaminated letters. Because of an inadequate local first response system for bioterrorism and no obvious command structure, public health and health care professionals struggled to establish lines of authority while giving the best treatment available to those who had either fallen ill with anthrax or had been exposed to it. Although there have been only 22 confirmed cases of anthrax or suspected anthrax resulting in 5 deaths, it took several days before the first case of anthrax was recognized as intentional. Moreover, the American public received mixed messages about the disease from a variety of government sources. Indeed, until the proliferation of anthrax cases in the post office, it was not even recognized that anthrax could be released from sealed envelopes. Clearly, the public health system is inadequately prepared to deal with bioterrorist
From the Center for the Study of Bioterrorism and Emerging Infections, Saint Louis University School of Public Health, St. Louis, Missouri (RGE, BS, BC); Oklahoma State Department of Health, Oklahoma City, Oklahoma (JMC); and the Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (MSB). Correspondence: Dr. Gregory Evans, Center for the Study of Bioterrorism and Emerging Infections, Saint Louis University School of Public Health, 3545 Lafayette Av., St. Louis, MO 63104 (E-mail: [email protected]). THE AMERICAN JOURNAL OF THE MEDICAL SCIENCES
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sures should be implemented. This initial response must come from the local level, yet local public health and medical care personnel have few resources to carry it out. The President and Congress are proposing to spend billions of dollars to increase the federal stockpile of antibiotics and vaccines and to develop detection devices and new medical treatments for BT agents, yet they have failed to earmark sufficient funds to improve the infrastructure and response capacity of state and local public health departments, hospitals, and clinicians who would put the treatments and technology to use. The President’s proposed 2003 budget addresses some of these concerns; however, the focus is still on first responders, new technologies, and stockpiling more vaccines and other medications. More resources must be placed in the hands of local health departments and hospitals. We should not minimize the importance of federal stockpiling of medical equipment, antibiotics, and vaccines. At best, however, these supplies can be delivered only after a minimum of 12 hours and, more realistically, after a full 24 hours. What will happen during that vital interim period as the local public health system waits to receive federal support? The devastating impact of diseases caused by BT agents or the injuries resulting from a conventional attack does not wait, nor does the panic that ensues after a large-scale terrorist attack. In the crucial time after an attack, everything must be handled on the local level, yet this is our weakest link. For every dollar spent to combat terrorism in the United States, less than a penny goes to local public health and health care preparedness. This failure to develop local public health response systems is even more unfortunate given that money spent on upgrading the infrastructure of local public health will not only prepare us for a terrorist incident but also allow us to upgrade our public health system. Most importantly, it will support the development of a surveillance system to detect and control naturally occurring infectious diseases. Now that terrorism is on the front burner of the political agenda, we must establish adequate funding to train and equip state and local public health agencies, hospitals, and physicians. Terrorism in a Historical Context The US Federal Bureau of Investigation defines terrorism as “the unlawful use of force and violence against persons or property to intimidate or coerce a government, the civilian population, or any segment thereof, in furtherance of political or social objectives.”1 Walter Laqueur2 traces the term “terrorism” back to 1798; however, the use of terrorist tactics precedes even this. A group called the sicarii, employing what we would define as terrorist tactics, was active in Palestine from 66 –73 CE. This highly 292
organized religious sect used tactics considered unorthodox at the time, such as attacking people in crowds with knives during holiday celebrations.2 During the French and Indian War of 1763, British forces gave smallpox-contaminated blankets to Native Americans. During World War I, the German bioweapons program developed anthrax, glanders, cholera, and wheat fungus as weapons targeting cavalry animals. In World War II, the Japanese tested biological weapons on Chinese prisoners.3 The United Kingdom operated an offensive bioweapons program until 1957, the United States until 1969, and the former Soviet Union until 1990. Iraq started its bioweapons program in 1985 and continues to develop bioweapons today.3 At least 17 other nations are currently suspected of operating offensive bioweapons programs. We have recently learned much about the Soviet bioweapons effort from Ken Alibek, who administered their smallpox bioweapons program. During testimony to the House Armed Services Committee in 1999, Alibek stated that the Soviet program was developing bioagents with no known prevention or cure and that during the height of the Soviets’ program, it employed more than 60,000 people.4 More than 12,000 of these were senior technicians or scientists who might have the knowledge to build a bioweapon on their own. Since the dissolution of the Soviet Union, many of these scientists have been unable to find employment and might be looking for work outside the country.4 Countries, such as Iraq and North Korea, that are interested in developing their own bioweapons or nuclear programs could employ these scientists and develop weapons that could be used by terrorist groups. Not only would they gain access to classified information but also former Soviet scientists might provide small amounts of microorganisms that could be used to seed a bioweapons program. Origins of Terrorism Terrorist have many motivations: psychological, ideological, and theological.5 We do not know who mailed anthrax spores to a US congressman and the news media, or why. We do not know whether the anthrax came from a state-sponsored program, an ideological extremist group, religious fanatics, or an individual terrorist with an unknown motivation. A person or group who has the ability to produce, buy, or steal the anthrax spores that were delivered in those letters probably has the ability to obtain a more lethal means of dispersion. Intelligence sources indicate that Osama bin Laden is interested in procuring both biological and nuclear weapons. He also has the financial resources to buy or develop these weapons and to hire scientists and technicians for these programs. If he cannot find personnel, he can train his own by sending June 2002 Volume 323 Number 6
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his people to the United States, Great Britain, or Germany to study the physics and microbiology necessary to develop mass casualty weapons. But most importantly, bin Laden and his al Qaeda network have developed a religious and political rationale to use these weapons. In 1999, bin Laden stated that “hostility toward America is a religious duty, and we hope to be awarded for it by God. I am confident that Muslims will be able to end the legend of the socalled super power that is America.”6 Another group of religious extremists, the Aum Shinrikyo, was responsible for the 1995 sarin gas attacks in a Tokyo subway in which a dozen people died and thousands were injured. Shoko Asahara, who saw himself as a messiah, founded the group in the late 1980s. His theology sanctioned mass murder, and by the end of 1995, his group had assets in excess of $1 billion. Scientists working for Aum Shinrikyo had attempted to make weapons from anthrax and botulinum. After many failures, Seichi Endo, a group member who had done graduate work in chemistry and molecular biology, produced the sarin gas that was used in the subway attacks.3 Before October 2001, biological agents had been used twice by terrorists in this country. On September 9, 1984, cases of food poisoning with Salmonella typhimurium occurred in The Dalles, Oregon.3 By the end of the attack, more than 1000 people reported gastrointestinal symptoms, and 751 had cultured confirmed or clinical salmonellosis. No deaths occurred. By late November 1984, no source had been found, and the deputy state epidemiologist stated that there was no evidence of a deliberate attempt at food poisoning. It was not until a year later that authorities determined that the food poisoning was a deliberate attempt by a religious cult to influence local elections. It was also determined that the group had experimented with a variety of other poisons, chemicals, and bacteria.3 In October 1996, 12 laboratory workers in a Texas medical center developed acute, severe diarrhea caused by Shigella dysenteriae. This outbreak was traced to intentionally contaminated food in the laboratory break room.7 Why Is the Threat of Terrorism Increasing? Five years ago, the US government spent $6.5 billion to protect the nation against terrorism, with only $16 million allocated to the Department of Health and Human Services (DHHS) terrorism initiatives. The 2000 –2001 budget devoted more than $9 billion dollars to fighting terrorism, with $265 million allocated to DHHS terrorism initiatives. This 16-fold increase resulted in part from national recognition that a technology renaissance exists in which new discoveries in biology, chemistry, and engineering increase the likelihood that a nation, group, or person could build and deploy a terrorist THE AMERICAN JOURNAL OF THE MEDICAL SCIENCES
weapon. With increasing knowledge available daily from journal articles, books, and the Internet, terrorists will no longer need to depend on traditional weapons to unleash terror. They have, or will soon have nuclear, chemical, and biological weapons. These weapons might not be military grade, but terrorists do not need a perfect weapon; all they need is a crude weapon that can kill and cause panic.8 Producing more and larger weapons adequately makes up for what is lost in lethality per weapon. The threat of terrorism is further increased by the availability of seed cultures that can be employed in acts of biological terrorism. The World Dictionary of Collections of Cultures and Microorganisms notes that there are 453 repositories worldwide in 67 nations that store all types of microorganisms. Fiftyfour and 18 of these sites will sell and ship anthrax and plague, respectively. The United States has not been fully successful in restricting the sale of potential bioterrorism agents. Even if the regulatory processes in this country are strengthened, terrorists can still obtain these organisms. The recent use of anthrax in the United States serves as a timely example of this. The bombing of the World Trade Center and the anthrax poisonings were unconventional in that it was not expected that terrorists would use jets as bombs or send a biological agent through the mail. Although the country must protect itself from a repeat of these events, it is likely that the next terrorist attack will take an entirely different form. We must be aware that if a biological agent is used, few physicians will be familiar with the disease it might cause. For example, very few US physicians have ever seen inhalational anthrax. Before this attack, only 18 cases of inhalational anthrax had been reported in this country, with the last one documented more than 25 years ago.9 Furthermore, because the diseases caused by agents of bioterrorism are so uncommon, physicians do not receive adequate training in medical school on how to deal with them. Nonetheless, an effective early warning and surveillance system will require alert and astute clinicians, especially primary care providers.10 Today’s terrorists have greater access to increasingly deadlier weapons, and the face of terrorism has changed as well.8 Historically, terrorists relied on acts that resulted in few casualties but high visibility. They were less interested in killing than in making a political statement. Today’s terrorists focus on inflicting mass casualties. If we had any doubts about this, the World Trade Center bombings should put them to rest. We must now rethink our antiterrorism priorities, taking into account the goal of killing large numbers of people. Biological weapons are of interest to terrorist groups not only because of their killing potential but also because it costs much less to kill a thousand 293
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people with biological weapons than with conventional weapons.8 For example, it requires only $1 to kill with aerosolized anthrax spores; the same death toll would require $2000 with conventional weapons, $800 with nuclear weapons, and $600 with chemical weapons (these estimates were from a 1970 study; although the dollar amounts would be different for 2002, the relative cost of the weapons remains approximately the same). Additionally, biological agents are considerably more lethal per gram than chemical agents. It would take approximately 100 g/kg sarin gas to kill 50% of exposed people, whereas botulinum toxin would require only 0.001 g/kg to have the same 50% lethality. There are other reasons for terrorists to use biological weapons. The threat of bioterrorism alone is likely to create panic, as we have seen with the anthrax attacks. Even though there were only a few deaths, there was widespread panic across the United States, with many types of white powder being reported to US law enforcement as possible anthrax. Primary Agents of Bioterrorism Terrorists have several agents from which to choose, and many of these have common features. They can be delivered as a weapon in liquid or powder form, and they can be dispersed successfully as an aerosol and in particle size needed to enter the lungs. The particles can be aerosolized from a line or point source either outdoors or indoors. Weather is a key factor for the successful outdoor release of any type of aerosolized biological agent. Atmospheric inversions would maximize the killing potential of an agent. An inversion causes stagnation of air movement allowing an aerosolized BT agent to remain suspended in the atmosphere longer. Another common characteristic of many biological agents is that they can be delivered in contaminated food or water. Food contamination is somewhat easier to achieve than water. Introducing a biological agent into a large body of water, such as a reservoir, leads to significant dilution, and the chlorine in water supplies kills most of the bacteriological agents that might be used by a terrorist. The introduction of a biological agent into the food supply might be easier and could potentially expose a large number of people. However, unless all the people ate the contaminated food simultaneously, they would get ill at different times. This illness would be recognized fairly rapidly and result in a recall of the food. We have modeled a release of 5 pounds of anthrax from the top of a building in downtown St. Louis, Missouri. Five pounds is a moderate amount of anthrax, particularly compared with the 2 to 3 ounces contained in the letter sent to Senator Daschle. A 294
well-trained person or group could produce 5 pounds in a relatively small lab, and it need not be weapons grade. Assuming that only a small proportion of the spores were in the range of 1 to 5 m, there would be enough available to enter the lungs of thousands of victims. Furthermore, the model uses actual census data and climatic conditions averaged over a 7-year period. It is assumed that the anthrax spores would travel due west from the city. On the basis of this model, approximately 62,000 persons would be killed. Approximately 50% of the St. Louis residents within the center of the path would die, with fewer casualties occurring further away from the source. If the terrorists planned their release during an atmospheric inversion, the number of deaths could be even higher. The number of casualties might be understated because it is assumed that 2,500 to 55,000 anthrax spores are required to cause disease. Evidence from the mailed anthrax attack suggests that fewer spores suffice for infectivity. NATO has identified 31 potential agents that could be used in a biological attack. The United States Army Medical Research Institute of Infectious Diseases (USAMRIID) has further reduced this list to 6 primary agents.11 This choice was based upon 5 criteria: availability of the agent, ease of production, lethality, infectivity, and stability. Agents that have high infectivity and lethality would be the most desirable to a terrorist. The 6 most likely agents for a biological attack selected by USAMRIID are divided into 3 categories. Category 1 agents are those that cause anthrax and smallpox; category 2 agents cause plague and tularemia; and category 3 includes botulinum toxin and agents of viral hemorrhagic fever.11 Category 1 agents rank the highest on a scale based on the USAMRIID criteria. It is interesting that anthrax ranks highest on the list and this was the first lethal BT agent used in this country. Because the spores were delivered through the mail, they were poorly aerosolized; thus, the lethality per gram of anthrax was relatively low. Smallpox is also a category 1 agent because it can be transmitted person to person and has the potential for aerosolization. A terrorist could aerosolize a suspension of smallpox virus that could infect at very low doses. These infected persons would then infect others within 7 to 12 days, and an epidemic could be started before public health authorities were able to respond. It spreads easily through respiratory droplets or direct contact with contaminated clothing or bed linens. It is estimated that the attack rate for unvaccinated contacts is 25 to 40%. Because of this high attack rate, it will be necessary to quarantine infected persons. Quarantine will be a major role for public health. Another agent of concern is Yersinia pestis (plague), because it too could be released by aerosol. June 2002 Volume 323 Number 6
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Historically, 3 recorded plague pandemics have killed more than 200 million people, most notably the Black Death epidemic in 14th century Europe. Before the 1950s, the organism had been studied by Japan and the United States as a potential bioweapon. Its least common but most severe form is primary pneumonic plague, which carries an overall mortality of nearly 60%. This is the most likely form a BT attack would take. Although mortality rates are high, they can be reduced substantially if antibiotic therapy is initiated within 18 to 24 hours of symptom onset.11,12 Francisella tularensis (tularemia) is another likely agent to be used by BTs. The organism has been weaponized by the United States (before the termination of its bioweapons program) and possibly by other countries. Six forms of tularemia are classified by clinical presentation and determined by route of exposure.11,12 The pneumonic form is the one most likely to be observed because it results from aerosolization of the bacteria and has a 30 to 60% untreated mortality. Although there is a live attenuated vaccine available, it is not recommended for generalized postexposure prophylaxis.11,12 Another bacterial agent of concern is Clostridium botulinum. Botulinum toxin is the most potent toxin known to man.11,12 Like anthrax, botulinum toxin was a major target of the Iraqi bioweapons program. As with the other BT agents, inhalation would be the most likely route of exposure; however, botulinum toxin could be added to food. The inhalational form is not seen naturally, and its presence is therefore a likely indication of bioterrorism. Because the inhalational form of botulism has not been studied in humans, the case mortality rate is not known. The last agents are the hemorrhagic fever viruses, of which the Ebola and Marburg viruses are probably the most familiar examples. Naturally occurring viral hemorrhagic fever is transmitted by contact with infected blood or secretions. However, airborne virus has been suspected of causing disease in primates and possibly in humans. Terrorists would need to develop an aerosolized form of the virus to have an effective bioweapon. Treatment for most of these diseases is largely supportive.9,11 The mere threat of terrorism is sufficient to cause major social disruptions. In 1997 the mailroom at the B’nai B’rith offices in Washington DC received a leaking package that contained a Petri dish marked “antrax.” It was early in our understanding of BT agents, and the first responders did not know that bacteria on a Petri dish are not a likely source of exposure and do not require decontamination. This was proven to be a hoax, but it managed to shut down Washington DC. Furthermore, it subjected a number of people to the embarrassment of undergoing decontamination in front of the news media. Since the discovery of anthrax-tainted mail, thousands of hoaxes all across the country have closed THE AMERICAN JOURNAL OF THE MEDICAL SCIENCES
down schools, businesses, and government offices, resulting in millions of dollars of expenses and lost revenue. In some cases, there has been a total failure to report suspicious situations that could indicate a possible BT. In 1997, 700 passengers arrived at Sun Harbor Airport in Phoenix, Arizona, from Acapulco, Mexico. More than 50 of the passengers had diarrhea. Emergency Medical Service personnel offloaded 25 passengers to ambulances, and 6 of these passengers were admitted to a local hospital. County health officers, who should have been informed of this immediately, learned of this event only after listening to the radio Monday morning. By the time the health department became involved, the victims had been released from the hospital, there were no stool samples to determine what might have caused the disease, and the airplane itself had been thoroughly cleaned. No one recorded the names of the sick passengers. Had this been a BT attack instead of simple food poisoning, the public health service would have been notified too late to mount an effective intervention, particularly if the disease had been contagious. The bombing of the World Trade Center and the mailing of anthrax spores have provided many lessons. We know that terrorists can be well-organized, can execute an attack employing dozens of operatives over an extended period, and can go undetected by current counter-terrorism efforts. We cannot depend on past experiences with terrorism to predict what terrorists will do in the future. The United States and other countries need an infrastructure that responds quickly to avoid repeating mistakes, such as informing the public that anthrax spores cannot be released from sealed envelopes, that transmission of spores from a secondary source is unlikely, or that a case of inhalational anthrax is probably the result of naturally acquired infection. Government must provide the public with accurate, timely, and coordinated information. Otherwise, the public will be suspicious and panic will increase as the terrorist event progresses. Preparing for Terrorism: The Role of Public Health It is clear that our nation’s public health system must play a lead role in preparing for the threat of chemical and biological terrorism. Public health has a long history of addressing similar challenges responding to naturally occurring infectious diseases and disasters. Also, the public health infrastructure has primary responsibility for coordinating efforts to address health issues that affect large populations and require the collaboration of multiple and diverse partners. Both of these areas of expertise are critical in our efforts to prepare for and respond to terrorism. However, the US public health infrastructure is already severely strained, and additional resources 295
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are required to meet the extensive challenges posed by chemical and biological terrorism. To prepare for the challenges posed by terrorism, several features of a chemical/biological attack should be considered. Some are common to both chemical and biological agents; others are specific to one or the other. First, a biological event will probably not be detected at the time it occurs and will be noticed only days later, when people fall ill. Second, the potential exists for many casualties, including those with severe illness and death because of direct exposure and those who represent psychogenic casualties. Third, first responders and health care workers are at risk for personal injury, primarily as a result of the dermal activity of chemical agents and the communicability of biological agents. Fourth, because an act of terrorism is a criminal event, public health must work with law enforcement to preserve evidence and conduct investigations. Finally, response efforts cross all jurisdictions (including local, state, and federal agencies), all medical and public health professions (including health professions schools, emergency management, hospitals, laboratories), the military, the media, fire departments, and law enforcement. The response to chemical and biological terrorist events require specialized planning as outlined in several recent documents.12–15 Critical to the success of such plans is a sensitive surveillance system capable of early detection of a BT event. An infectious disease surveillance system for the monitoring and control of endemic diseases has been functioning in the United States for decades. Participants include local and state health departments, laboratories, infection control practitioners in medical facilities, and clinicians. This system can and must be enhanced so it can rapidly identify BT events. Clinicians are critical in this effort as they are usually first to recognize and report such events. Educating clinicians to recognize potential terrorism-related diseases and to report such incidents is a major component of preparedness and a principal goal of this symposium issue. The current surveillance system focuses primarily on the identification and reporting of specific diseases. Recent surveillance efforts in the United States and elsewhere have been aimed at identifying unusual disease occurrences by employing “syndromic surveillance” of emergency departments, emergency/911, and poison control centers, and by real-time analysis of hospital census and discharge data. Also, the Centers for Disease Control and Prevention’s National Electronic Disease Surveillance System (NEDSS) project provides funds to help states develop electronic modalities to improve the speed of reporting. Nonetheless, as these systems are evolving, the first line of surveillance must be the astute physician. Physicians must be able to recognize the signs and symptoms caused by a biological agent 296
and report the suspected case to public health authorities. Another major challenge is to enhance our ability to respond rapidly to mass casualty events. We must be able to provide treatment to persons with disease and initiate preventive measures for persons who may have been exposed. We must disseminate information and recommendations to the worried well. Many of the potential BT agents can cause lifethreatening disease and require intensive hospital care. We must consider the local availability of ICU beds, ventilators, drugs, and medical professionals to treat potentially hundreds or thousands of critically ill persons. However, in any bioterrorism-related event, the number of potentially exposed persons will far exceed the number of actual cases, and these persons may require vaccines or prophylactic antibiotics to prevent disease from occurring. We must be prepared to deliver these interventions rapidly to thousands of persons through mass distribution sites in the community. The US National Pharmaceutical Stockpile (NPS) and similar systems throughout the world have been established to rapidly deliver supplies to states to meet treatment and prophylaxis needs. However, states must also have access to local resources to cope with the problems caused by small-scale events and to function during the first 12 to 48 hours before the arrival of the NPS. One perplexing challenge is the development of plans to prevent the spread of communicable BT agents. Persons with the disease will need isolation and those potentially exposed may need to be quarantined. Contingencies vary depending upon the communicability of the agent. They have been insignificant in the recent anthrax episodes but will be paramount in the event of a smallpox incident. Hospitals need to develop plans for evaluating and isolating a limited number of patients with confirmed or suspected communicable diseases, and communities must develop plans for isolating large numbers of such patients. The latter situation may require designating a hospital or other facility for communicable disease. Quarantining well persons raises even more problems. States must address the issue of determining legal authority to limit the movement of citizens and to enforce such orders. In the United States, the Centers for Disease Control and Prevention has provided guidance on these issues in 2 recent documents. “The Model State Emergency Powers Act” assists states in developing the legal authority to address issues like seizing hospitals for treating and isolating patients, quarantining exposed persons, and gaining access to medical records.16 The “Smallpox Response Plan and Guidelines” addresses more specifically the complex challenges related to the control of a smallpox epidemic.17 Clearly, public health law will be challenged in the face of a BT event.18,19 Gostin et al19 have argued that many states have existing public health statJune 2002 Volume 323 Number 6
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utes that are antiquated, fail to reflect modern scientific knowledge of disease, or do not reflect constitutionally mandated limits on the ability of a state to restrict individual liberties. As a consequence of a BT event, individual citizens might be forced to accept treatment or vaccinations to contain an epidemic. This clearly could create a significant challenge in balancing civil rights.18 The protection of health care workers and first responders will also require planning. Hospitals must consider several issues, such as having a stockpile of antibiotics to treat staff and patients in the case of a BT incident aimed at the hospital, infection control procedures for communicable BT agents, and the ability to decontaminate patients who have been exposed to chemical agents before entering the hospital.20,21 An important issue is the need to treat families of medical care staff to reduce staff need to return home to care for family members. A particularly challenging issue is the need for persons with immunity against smallpox to participate in the investigation and care of suspected or confirmed smallpox cases. The CDC has established teams to investigate potential smallpox outbreaks and has vaccinated those personnel against the disease. However, health care workers and first responders in communities will not have full immunity and will be at risk of contracting smallpox when caring for persons with the disease. The decision to vaccinate these personnel is complicated by of the risk of significant side effects from the vaccine. Another concern is the economic impact of responding to a BT event. Understanding the financial impact is important in developing a comprehensive public health policy. Kaufmann et al22 constructed an economic model comparing the impact of anthrax, tularemia, and Brucella species when released as aerosols in a suburban city.22 The model demonstrated that the economic impact of a BT event ranges from nearly $500 million/ 100,000 persons exposed to $26.2 billion/100,000 persons exposed depending on the agent. The authors concluded that the most important method to reduce these costs was an intact public health structure that could rapidly implement postexposure prophylaxis. Of major importance in responding to a BT event is the ability to rapidly identify the responsible agent. Thus, in the United States, the CDC has made the expansion of its Laboratory Response Network a high priority. Efforts to employ advanced technologies in the development of sensitive and rapid tests for likely BT agents continue. These procedures are being made available to state public health laboratories, which now have the capacity to rapidly diagnose anthrax, plague, and tularemia. Arguably, the most notable deficiency in response to the recent BT events in the United States was the inability to provide timely and accurate information THE AMERICAN JOURNAL OF THE MEDICAL SCIENCES
to the public and to the numerous professionals involved in response activities. Effective communication is a fundamental element of all aspects of public health and is critical for the rapid recognition of, response to, and recovery from public health emergencies. The CDC and state public health agencies are striving to establish a Health Alert Network that would provide essential communication skills and technologies to all jurisdictions in the United States. Major issues to address will include public information, communicating to health professionals, press and public affairs, policy advocacy, and incident command. Public health professionals should establish a good working relationship with the local media, because the media will be critical in disseminating information to the public and to health professionals. References 1. Code of Federal Regulations Title 28 –Judicial Administration, Chapter I–Department of Justice, PART 0, Subpart P–Federal Bureau of Investigation, Section 0.85 General functions. 2. Laqueur W. A history of terrorism. New Brunswick (NJ): Transaction Publishers; 1977. 3. Miller M, Engelberg MS, Broad W. Germs: biological weapons and America’s secret war. New York: Simon and Schuster; 2001. 4. Alibek K, Handelman S. Biohazard. New York: Random House; 1999. 5. Reich W. Origins of terrorism. Baltimore: Woodrow Wilson Center Press; 1998. 6. Conversation with terror. TIME Magazine. 1999 Jan 11. 7. Kolavic SA, Kimura A, Simons SL, et al. An outbreak of Shigella dysenteriae type 2 among laboratory workers due to intentional food contamination. JAMA 1997;278:396 – 8. 8. Osterholm MT, Schwartz J. Living terrors: what America needs to know to survive the coming bioterrorist catastrophe. New York: Delacorte Press; 2000. 9. Jernigan JA, Stephens DS, Ashford DA, et al. Bioterrorism-related inhalational anthrax: the first 10 cases reported in the United States. Emerg Infect Dis 2001;7:933– 44. 10. Gerberding JL, Hughes JM, Koplan JP. Bioterrorism preparedness and response. JAMA 2002;287:898 –9. 11. Biological warfare and terrorism: medical issues and response. In: Medical management of biological casualties handbook (the “blue book”), 4th ed. Ft. Detrick (MD): United States Army Medical Research Institute of Infectious Diseases; 2000. 12. Anonymous. Biological and chemical terrorism: strategic plan for preparedness and response. Recommendations of the CDC Strategic Planning Workgroup. MMWR Recomm Rep 2000;49(RR-4):1–14. 13. Improving local and state response to terrorist incidents involving biological weapons: interim planning guide. Department of Defense, U.S. Army Soldier and Biological Chemical Command, Domestic Preparedness Office, Aberdeen Proving Ground, MD. 2000 Sep 12. Available at: URL: http:// www2.sbccom.army.mil/hld/bwirp/bwirp_interim_planning_ guide_download.htm. 14. Fraser MR, Fisher VS. Elements of effective bioterrorism preparedness: a planning primer for local public health agen-
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15.
16.
17.
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cies. Washington DC: National Association of County and City Health Officials; 2001. The public health response to biological and chemical terrorism: Interim planning guidance for state public health officials. Atlanta (GA): Centers for Disease Control and Prevention, July 2001. Available at: URL: http://www.bt.cdc.gov/ Documents/Planning/PlanningGuidance.pdf. The model state emergency health powers act. The Center for Law and the Public’s Health at Georgetown and Johns Hopkins Universities, for the Centers for Disease Control and Prevention. 2001 Oct 23. Available at: URL: http://www. .publichealthlaw.net/MSEHPA/MSEHPA.pdf. Interim smallpox response plan and guidelines. Draft 2.0. Atlanta (GA): Centers for Disease Control and Prevention; 2002 Jan 23. Available at: URL: http://www.bt.cdc.gov/ DocumentsApp/Smallpox/RPG/index.asp. Fidler DP. The malevolent use of microbes and the rule of law: legal challenges presented by bioterrorism. Clin Infect Dis 2001;33:686 –9.
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19. Gostin LO, Burris S, Lazzarini Z. The law and the public’s health: a study of infectious disease law in the United States. Columbia Law Rev 1999;99:59 –128. 20. English JF, Cundiff MY, Malone JD, et al. Bioterrorism readiness plan: a template for healthcare facilities. APIC Bioterrorism Task Force and CDC Hospital Infections Program Bioterrorism Working Group, April 1999. Available at: URL: http://www.cdc.gov/ncidod/hip/Bio/13apr99APICCDCBioterrorism.pdf. 21. California Hospital Bioterrorism Response Planning Guide. Sacramento: California Department of Health Services; 2001. Available at: URL: http://www.dhs.cahwnet. gov/BioTerrorism%20Headline/Revised%20BT%20Response%20master%20document.pdf. 22. Kaufmann AF, Meltzer MI, Schmid GP. The economic impact of a bioterrorist attack: are the prevention and postattack intervention programs justifiable? Emerg Infect Dis 1997;3:83–94.
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ABSTRACT: The use of biological and chemical weapons as agents of warfare and terrorism has occurred sporadically, but recent events demonstrate the increasing risk and possibility that terrorist groups with grievances against the government or groups may employ them. Historically, most evaluations of the potential risk for biological weaponry have focused on the military, but the recent release of anthrax in the United States demonstrates that civilian populations are also at risk. More likely than not, most bioterrorism events will be of a small scale; however,
agents such as Bacillus anthracis and Yersinia pestis could leave hundreds of thousands dead or incapacitated. The impact of the attack will depend on a number of variables, including the agent used, method of dispersal, and the responsiveness of the public health system. With any large-scale event, the public health infrastructure will be called upon to deal with mass casualties and the “worried well.” KEY INDEXING TERMS: Bioterrorism; Public health; Emerging infections; Bioweapons. [Am J Med Sci 2002;323(6):291–298.]
O
(BT) events. We do not have the command structure, the training, or the resources necessary for the task. Yet we are making advances in preparedness at the local level. Each day that passes since September 11 brings municipalities closer to having plans to deal with terrorism. Some of these advances will be discussed later in this article. Although first responders will be on the front lines of a terrorist attack that might employ conventional bombs, radiation, and chemicals, in a biological attack, they will play only a secondary role. In a BT attack, the people on the front lines will be the practicing physicians who will diagnose and treat diseases and public health epidemiologists and laboratory personnel who will determine who has been exposed. They will decide who should be treated and how, and they will provide the mechanism to rapidly disseminate this treatment. Furthermore, in the case of transmittable diseases, it is the public health epidemiologists who will determine who must be quarantined to prevent the spread of the disease. However, public health systems in the United States have received far less federal money to prepare for acts of terrorism than have traditional first responders. In fact, in most parts of the United States, local public health and medical care professionals have inadequate training and resources to respond to a major terrorist attack, whether conventional or biological. The 12 hours immediately after the detection of a BT attack are crucial for saving lives and minimizing public panic. Antibiotics and vaccines must be provided immediately to thousands of people potentially exposed to an airborne release of deadly bacteria or viruses. Law enforcement agencies and the National Guard must be told which quarantine mea-
n September 11, 2001, police, firefighters, and emergency medical technicians rushed to the scene of devastation at the World Trade Center. Their quick response and specialized training helped save thousands of lives, contained damage, and provided reassurance that a command and control structure was firmly in place. For more than 2 months, the country was terrorized by cases of anthrax originating from 3 contaminated letters. Because of an inadequate local first response system for bioterrorism and no obvious command structure, public health and health care professionals struggled to establish lines of authority while giving the best treatment available to those who had either fallen ill with anthrax or had been exposed to it. Although there have been only 22 confirmed cases of anthrax or suspected anthrax resulting in 5 deaths, it took several days before the first case of anthrax was recognized as intentional. Moreover, the American public received mixed messages about the disease from a variety of government sources. Indeed, until the proliferation of anthrax cases in the post office, it was not even recognized that anthrax could be released from sealed envelopes. Clearly, the public health system is inadequately prepared to deal with bioterrorist
From the Center for the Study of Bioterrorism and Emerging Infections, Saint Louis University School of Public Health, St. Louis, Missouri (RGE, BS, BC); Oklahoma State Department of Health, Oklahoma City, Oklahoma (JMC); and the Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (MSB). Correspondence: Dr. Gregory Evans, Center for the Study of Bioterrorism and Emerging Infections, Saint Louis University School of Public Health, 3545 Lafayette Av., St. Louis, MO 63104 (E-mail: [email protected]). THE AMERICAN JOURNAL OF THE MEDICAL SCIENCES
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sures should be implemented. This initial response must come from the local level, yet local public health and medical care personnel have few resources to carry it out. The President and Congress are proposing to spend billions of dollars to increase the federal stockpile of antibiotics and vaccines and to develop detection devices and new medical treatments for BT agents, yet they have failed to earmark sufficient funds to improve the infrastructure and response capacity of state and local public health departments, hospitals, and clinicians who would put the treatments and technology to use. The President’s proposed 2003 budget addresses some of these concerns; however, the focus is still on first responders, new technologies, and stockpiling more vaccines and other medications. More resources must be placed in the hands of local health departments and hospitals. We should not minimize the importance of federal stockpiling of medical equipment, antibiotics, and vaccines. At best, however, these supplies can be delivered only after a minimum of 12 hours and, more realistically, after a full 24 hours. What will happen during that vital interim period as the local public health system waits to receive federal support? The devastating impact of diseases caused by BT agents or the injuries resulting from a conventional attack does not wait, nor does the panic that ensues after a large-scale terrorist attack. In the crucial time after an attack, everything must be handled on the local level, yet this is our weakest link. For every dollar spent to combat terrorism in the United States, less than a penny goes to local public health and health care preparedness. This failure to develop local public health response systems is even more unfortunate given that money spent on upgrading the infrastructure of local public health will not only prepare us for a terrorist incident but also allow us to upgrade our public health system. Most importantly, it will support the development of a surveillance system to detect and control naturally occurring infectious diseases. Now that terrorism is on the front burner of the political agenda, we must establish adequate funding to train and equip state and local public health agencies, hospitals, and physicians. Terrorism in a Historical Context The US Federal Bureau of Investigation defines terrorism as “the unlawful use of force and violence against persons or property to intimidate or coerce a government, the civilian population, or any segment thereof, in furtherance of political or social objectives.”1 Walter Laqueur2 traces the term “terrorism” back to 1798; however, the use of terrorist tactics precedes even this. A group called the sicarii, employing what we would define as terrorist tactics, was active in Palestine from 66 –73 CE. This highly 292
organized religious sect used tactics considered unorthodox at the time, such as attacking people in crowds with knives during holiday celebrations.2 During the French and Indian War of 1763, British forces gave smallpox-contaminated blankets to Native Americans. During World War I, the German bioweapons program developed anthrax, glanders, cholera, and wheat fungus as weapons targeting cavalry animals. In World War II, the Japanese tested biological weapons on Chinese prisoners.3 The United Kingdom operated an offensive bioweapons program until 1957, the United States until 1969, and the former Soviet Union until 1990. Iraq started its bioweapons program in 1985 and continues to develop bioweapons today.3 At least 17 other nations are currently suspected of operating offensive bioweapons programs. We have recently learned much about the Soviet bioweapons effort from Ken Alibek, who administered their smallpox bioweapons program. During testimony to the House Armed Services Committee in 1999, Alibek stated that the Soviet program was developing bioagents with no known prevention or cure and that during the height of the Soviets’ program, it employed more than 60,000 people.4 More than 12,000 of these were senior technicians or scientists who might have the knowledge to build a bioweapon on their own. Since the dissolution of the Soviet Union, many of these scientists have been unable to find employment and might be looking for work outside the country.4 Countries, such as Iraq and North Korea, that are interested in developing their own bioweapons or nuclear programs could employ these scientists and develop weapons that could be used by terrorist groups. Not only would they gain access to classified information but also former Soviet scientists might provide small amounts of microorganisms that could be used to seed a bioweapons program. Origins of Terrorism Terrorist have many motivations: psychological, ideological, and theological.5 We do not know who mailed anthrax spores to a US congressman and the news media, or why. We do not know whether the anthrax came from a state-sponsored program, an ideological extremist group, religious fanatics, or an individual terrorist with an unknown motivation. A person or group who has the ability to produce, buy, or steal the anthrax spores that were delivered in those letters probably has the ability to obtain a more lethal means of dispersion. Intelligence sources indicate that Osama bin Laden is interested in procuring both biological and nuclear weapons. He also has the financial resources to buy or develop these weapons and to hire scientists and technicians for these programs. If he cannot find personnel, he can train his own by sending June 2002 Volume 323 Number 6
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his people to the United States, Great Britain, or Germany to study the physics and microbiology necessary to develop mass casualty weapons. But most importantly, bin Laden and his al Qaeda network have developed a religious and political rationale to use these weapons. In 1999, bin Laden stated that “hostility toward America is a religious duty, and we hope to be awarded for it by God. I am confident that Muslims will be able to end the legend of the socalled super power that is America.”6 Another group of religious extremists, the Aum Shinrikyo, was responsible for the 1995 sarin gas attacks in a Tokyo subway in which a dozen people died and thousands were injured. Shoko Asahara, who saw himself as a messiah, founded the group in the late 1980s. His theology sanctioned mass murder, and by the end of 1995, his group had assets in excess of $1 billion. Scientists working for Aum Shinrikyo had attempted to make weapons from anthrax and botulinum. After many failures, Seichi Endo, a group member who had done graduate work in chemistry and molecular biology, produced the sarin gas that was used in the subway attacks.3 Before October 2001, biological agents had been used twice by terrorists in this country. On September 9, 1984, cases of food poisoning with Salmonella typhimurium occurred in The Dalles, Oregon.3 By the end of the attack, more than 1000 people reported gastrointestinal symptoms, and 751 had cultured confirmed or clinical salmonellosis. No deaths occurred. By late November 1984, no source had been found, and the deputy state epidemiologist stated that there was no evidence of a deliberate attempt at food poisoning. It was not until a year later that authorities determined that the food poisoning was a deliberate attempt by a religious cult to influence local elections. It was also determined that the group had experimented with a variety of other poisons, chemicals, and bacteria.3 In October 1996, 12 laboratory workers in a Texas medical center developed acute, severe diarrhea caused by Shigella dysenteriae. This outbreak was traced to intentionally contaminated food in the laboratory break room.7 Why Is the Threat of Terrorism Increasing? Five years ago, the US government spent $6.5 billion to protect the nation against terrorism, with only $16 million allocated to the Department of Health and Human Services (DHHS) terrorism initiatives. The 2000 –2001 budget devoted more than $9 billion dollars to fighting terrorism, with $265 million allocated to DHHS terrorism initiatives. This 16-fold increase resulted in part from national recognition that a technology renaissance exists in which new discoveries in biology, chemistry, and engineering increase the likelihood that a nation, group, or person could build and deploy a terrorist THE AMERICAN JOURNAL OF THE MEDICAL SCIENCES
weapon. With increasing knowledge available daily from journal articles, books, and the Internet, terrorists will no longer need to depend on traditional weapons to unleash terror. They have, or will soon have nuclear, chemical, and biological weapons. These weapons might not be military grade, but terrorists do not need a perfect weapon; all they need is a crude weapon that can kill and cause panic.8 Producing more and larger weapons adequately makes up for what is lost in lethality per weapon. The threat of terrorism is further increased by the availability of seed cultures that can be employed in acts of biological terrorism. The World Dictionary of Collections of Cultures and Microorganisms notes that there are 453 repositories worldwide in 67 nations that store all types of microorganisms. Fiftyfour and 18 of these sites will sell and ship anthrax and plague, respectively. The United States has not been fully successful in restricting the sale of potential bioterrorism agents. Even if the regulatory processes in this country are strengthened, terrorists can still obtain these organisms. The recent use of anthrax in the United States serves as a timely example of this. The bombing of the World Trade Center and the anthrax poisonings were unconventional in that it was not expected that terrorists would use jets as bombs or send a biological agent through the mail. Although the country must protect itself from a repeat of these events, it is likely that the next terrorist attack will take an entirely different form. We must be aware that if a biological agent is used, few physicians will be familiar with the disease it might cause. For example, very few US physicians have ever seen inhalational anthrax. Before this attack, only 18 cases of inhalational anthrax had been reported in this country, with the last one documented more than 25 years ago.9 Furthermore, because the diseases caused by agents of bioterrorism are so uncommon, physicians do not receive adequate training in medical school on how to deal with them. Nonetheless, an effective early warning and surveillance system will require alert and astute clinicians, especially primary care providers.10 Today’s terrorists have greater access to increasingly deadlier weapons, and the face of terrorism has changed as well.8 Historically, terrorists relied on acts that resulted in few casualties but high visibility. They were less interested in killing than in making a political statement. Today’s terrorists focus on inflicting mass casualties. If we had any doubts about this, the World Trade Center bombings should put them to rest. We must now rethink our antiterrorism priorities, taking into account the goal of killing large numbers of people. Biological weapons are of interest to terrorist groups not only because of their killing potential but also because it costs much less to kill a thousand 293
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people with biological weapons than with conventional weapons.8 For example, it requires only $1 to kill with aerosolized anthrax spores; the same death toll would require $2000 with conventional weapons, $800 with nuclear weapons, and $600 with chemical weapons (these estimates were from a 1970 study; although the dollar amounts would be different for 2002, the relative cost of the weapons remains approximately the same). Additionally, biological agents are considerably more lethal per gram than chemical agents. It would take approximately 100 g/kg sarin gas to kill 50% of exposed people, whereas botulinum toxin would require only 0.001 g/kg to have the same 50% lethality. There are other reasons for terrorists to use biological weapons. The threat of bioterrorism alone is likely to create panic, as we have seen with the anthrax attacks. Even though there were only a few deaths, there was widespread panic across the United States, with many types of white powder being reported to US law enforcement as possible anthrax. Primary Agents of Bioterrorism Terrorists have several agents from which to choose, and many of these have common features. They can be delivered as a weapon in liquid or powder form, and they can be dispersed successfully as an aerosol and in particle size needed to enter the lungs. The particles can be aerosolized from a line or point source either outdoors or indoors. Weather is a key factor for the successful outdoor release of any type of aerosolized biological agent. Atmospheric inversions would maximize the killing potential of an agent. An inversion causes stagnation of air movement allowing an aerosolized BT agent to remain suspended in the atmosphere longer. Another common characteristic of many biological agents is that they can be delivered in contaminated food or water. Food contamination is somewhat easier to achieve than water. Introducing a biological agent into a large body of water, such as a reservoir, leads to significant dilution, and the chlorine in water supplies kills most of the bacteriological agents that might be used by a terrorist. The introduction of a biological agent into the food supply might be easier and could potentially expose a large number of people. However, unless all the people ate the contaminated food simultaneously, they would get ill at different times. This illness would be recognized fairly rapidly and result in a recall of the food. We have modeled a release of 5 pounds of anthrax from the top of a building in downtown St. Louis, Missouri. Five pounds is a moderate amount of anthrax, particularly compared with the 2 to 3 ounces contained in the letter sent to Senator Daschle. A 294
well-trained person or group could produce 5 pounds in a relatively small lab, and it need not be weapons grade. Assuming that only a small proportion of the spores were in the range of 1 to 5 m, there would be enough available to enter the lungs of thousands of victims. Furthermore, the model uses actual census data and climatic conditions averaged over a 7-year period. It is assumed that the anthrax spores would travel due west from the city. On the basis of this model, approximately 62,000 persons would be killed. Approximately 50% of the St. Louis residents within the center of the path would die, with fewer casualties occurring further away from the source. If the terrorists planned their release during an atmospheric inversion, the number of deaths could be even higher. The number of casualties might be understated because it is assumed that 2,500 to 55,000 anthrax spores are required to cause disease. Evidence from the mailed anthrax attack suggests that fewer spores suffice for infectivity. NATO has identified 31 potential agents that could be used in a biological attack. The United States Army Medical Research Institute of Infectious Diseases (USAMRIID) has further reduced this list to 6 primary agents.11 This choice was based upon 5 criteria: availability of the agent, ease of production, lethality, infectivity, and stability. Agents that have high infectivity and lethality would be the most desirable to a terrorist. The 6 most likely agents for a biological attack selected by USAMRIID are divided into 3 categories. Category 1 agents are those that cause anthrax and smallpox; category 2 agents cause plague and tularemia; and category 3 includes botulinum toxin and agents of viral hemorrhagic fever.11 Category 1 agents rank the highest on a scale based on the USAMRIID criteria. It is interesting that anthrax ranks highest on the list and this was the first lethal BT agent used in this country. Because the spores were delivered through the mail, they were poorly aerosolized; thus, the lethality per gram of anthrax was relatively low. Smallpox is also a category 1 agent because it can be transmitted person to person and has the potential for aerosolization. A terrorist could aerosolize a suspension of smallpox virus that could infect at very low doses. These infected persons would then infect others within 7 to 12 days, and an epidemic could be started before public health authorities were able to respond. It spreads easily through respiratory droplets or direct contact with contaminated clothing or bed linens. It is estimated that the attack rate for unvaccinated contacts is 25 to 40%. Because of this high attack rate, it will be necessary to quarantine infected persons. Quarantine will be a major role for public health. Another agent of concern is Yersinia pestis (plague), because it too could be released by aerosol. June 2002 Volume 323 Number 6
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Historically, 3 recorded plague pandemics have killed more than 200 million people, most notably the Black Death epidemic in 14th century Europe. Before the 1950s, the organism had been studied by Japan and the United States as a potential bioweapon. Its least common but most severe form is primary pneumonic plague, which carries an overall mortality of nearly 60%. This is the most likely form a BT attack would take. Although mortality rates are high, they can be reduced substantially if antibiotic therapy is initiated within 18 to 24 hours of symptom onset.11,12 Francisella tularensis (tularemia) is another likely agent to be used by BTs. The organism has been weaponized by the United States (before the termination of its bioweapons program) and possibly by other countries. Six forms of tularemia are classified by clinical presentation and determined by route of exposure.11,12 The pneumonic form is the one most likely to be observed because it results from aerosolization of the bacteria and has a 30 to 60% untreated mortality. Although there is a live attenuated vaccine available, it is not recommended for generalized postexposure prophylaxis.11,12 Another bacterial agent of concern is Clostridium botulinum. Botulinum toxin is the most potent toxin known to man.11,12 Like anthrax, botulinum toxin was a major target of the Iraqi bioweapons program. As with the other BT agents, inhalation would be the most likely route of exposure; however, botulinum toxin could be added to food. The inhalational form is not seen naturally, and its presence is therefore a likely indication of bioterrorism. Because the inhalational form of botulism has not been studied in humans, the case mortality rate is not known. The last agents are the hemorrhagic fever viruses, of which the Ebola and Marburg viruses are probably the most familiar examples. Naturally occurring viral hemorrhagic fever is transmitted by contact with infected blood or secretions. However, airborne virus has been suspected of causing disease in primates and possibly in humans. Terrorists would need to develop an aerosolized form of the virus to have an effective bioweapon. Treatment for most of these diseases is largely supportive.9,11 The mere threat of terrorism is sufficient to cause major social disruptions. In 1997 the mailroom at the B’nai B’rith offices in Washington DC received a leaking package that contained a Petri dish marked “antrax.” It was early in our understanding of BT agents, and the first responders did not know that bacteria on a Petri dish are not a likely source of exposure and do not require decontamination. This was proven to be a hoax, but it managed to shut down Washington DC. Furthermore, it subjected a number of people to the embarrassment of undergoing decontamination in front of the news media. Since the discovery of anthrax-tainted mail, thousands of hoaxes all across the country have closed THE AMERICAN JOURNAL OF THE MEDICAL SCIENCES
down schools, businesses, and government offices, resulting in millions of dollars of expenses and lost revenue. In some cases, there has been a total failure to report suspicious situations that could indicate a possible BT. In 1997, 700 passengers arrived at Sun Harbor Airport in Phoenix, Arizona, from Acapulco, Mexico. More than 50 of the passengers had diarrhea. Emergency Medical Service personnel offloaded 25 passengers to ambulances, and 6 of these passengers were admitted to a local hospital. County health officers, who should have been informed of this immediately, learned of this event only after listening to the radio Monday morning. By the time the health department became involved, the victims had been released from the hospital, there were no stool samples to determine what might have caused the disease, and the airplane itself had been thoroughly cleaned. No one recorded the names of the sick passengers. Had this been a BT attack instead of simple food poisoning, the public health service would have been notified too late to mount an effective intervention, particularly if the disease had been contagious. The bombing of the World Trade Center and the mailing of anthrax spores have provided many lessons. We know that terrorists can be well-organized, can execute an attack employing dozens of operatives over an extended period, and can go undetected by current counter-terrorism efforts. We cannot depend on past experiences with terrorism to predict what terrorists will do in the future. The United States and other countries need an infrastructure that responds quickly to avoid repeating mistakes, such as informing the public that anthrax spores cannot be released from sealed envelopes, that transmission of spores from a secondary source is unlikely, or that a case of inhalational anthrax is probably the result of naturally acquired infection. Government must provide the public with accurate, timely, and coordinated information. Otherwise, the public will be suspicious and panic will increase as the terrorist event progresses. Preparing for Terrorism: The Role of Public Health It is clear that our nation’s public health system must play a lead role in preparing for the threat of chemical and biological terrorism. Public health has a long history of addressing similar challenges responding to naturally occurring infectious diseases and disasters. Also, the public health infrastructure has primary responsibility for coordinating efforts to address health issues that affect large populations and require the collaboration of multiple and diverse partners. Both of these areas of expertise are critical in our efforts to prepare for and respond to terrorism. However, the US public health infrastructure is already severely strained, and additional resources 295
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are required to meet the extensive challenges posed by chemical and biological terrorism. To prepare for the challenges posed by terrorism, several features of a chemical/biological attack should be considered. Some are common to both chemical and biological agents; others are specific to one or the other. First, a biological event will probably not be detected at the time it occurs and will be noticed only days later, when people fall ill. Second, the potential exists for many casualties, including those with severe illness and death because of direct exposure and those who represent psychogenic casualties. Third, first responders and health care workers are at risk for personal injury, primarily as a result of the dermal activity of chemical agents and the communicability of biological agents. Fourth, because an act of terrorism is a criminal event, public health must work with law enforcement to preserve evidence and conduct investigations. Finally, response efforts cross all jurisdictions (including local, state, and federal agencies), all medical and public health professions (including health professions schools, emergency management, hospitals, laboratories), the military, the media, fire departments, and law enforcement. The response to chemical and biological terrorist events require specialized planning as outlined in several recent documents.12–15 Critical to the success of such plans is a sensitive surveillance system capable of early detection of a BT event. An infectious disease surveillance system for the monitoring and control of endemic diseases has been functioning in the United States for decades. Participants include local and state health departments, laboratories, infection control practitioners in medical facilities, and clinicians. This system can and must be enhanced so it can rapidly identify BT events. Clinicians are critical in this effort as they are usually first to recognize and report such events. Educating clinicians to recognize potential terrorism-related diseases and to report such incidents is a major component of preparedness and a principal goal of this symposium issue. The current surveillance system focuses primarily on the identification and reporting of specific diseases. Recent surveillance efforts in the United States and elsewhere have been aimed at identifying unusual disease occurrences by employing “syndromic surveillance” of emergency departments, emergency/911, and poison control centers, and by real-time analysis of hospital census and discharge data. Also, the Centers for Disease Control and Prevention’s National Electronic Disease Surveillance System (NEDSS) project provides funds to help states develop electronic modalities to improve the speed of reporting. Nonetheless, as these systems are evolving, the first line of surveillance must be the astute physician. Physicians must be able to recognize the signs and symptoms caused by a biological agent 296
and report the suspected case to public health authorities. Another major challenge is to enhance our ability to respond rapidly to mass casualty events. We must be able to provide treatment to persons with disease and initiate preventive measures for persons who may have been exposed. We must disseminate information and recommendations to the worried well. Many of the potential BT agents can cause lifethreatening disease and require intensive hospital care. We must consider the local availability of ICU beds, ventilators, drugs, and medical professionals to treat potentially hundreds or thousands of critically ill persons. However, in any bioterrorism-related event, the number of potentially exposed persons will far exceed the number of actual cases, and these persons may require vaccines or prophylactic antibiotics to prevent disease from occurring. We must be prepared to deliver these interventions rapidly to thousands of persons through mass distribution sites in the community. The US National Pharmaceutical Stockpile (NPS) and similar systems throughout the world have been established to rapidly deliver supplies to states to meet treatment and prophylaxis needs. However, states must also have access to local resources to cope with the problems caused by small-scale events and to function during the first 12 to 48 hours before the arrival of the NPS. One perplexing challenge is the development of plans to prevent the spread of communicable BT agents. Persons with the disease will need isolation and those potentially exposed may need to be quarantined. Contingencies vary depending upon the communicability of the agent. They have been insignificant in the recent anthrax episodes but will be paramount in the event of a smallpox incident. Hospitals need to develop plans for evaluating and isolating a limited number of patients with confirmed or suspected communicable diseases, and communities must develop plans for isolating large numbers of such patients. The latter situation may require designating a hospital or other facility for communicable disease. Quarantining well persons raises even more problems. States must address the issue of determining legal authority to limit the movement of citizens and to enforce such orders. In the United States, the Centers for Disease Control and Prevention has provided guidance on these issues in 2 recent documents. “The Model State Emergency Powers Act” assists states in developing the legal authority to address issues like seizing hospitals for treating and isolating patients, quarantining exposed persons, and gaining access to medical records.16 The “Smallpox Response Plan and Guidelines” addresses more specifically the complex challenges related to the control of a smallpox epidemic.17 Clearly, public health law will be challenged in the face of a BT event.18,19 Gostin et al19 have argued that many states have existing public health statJune 2002 Volume 323 Number 6
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utes that are antiquated, fail to reflect modern scientific knowledge of disease, or do not reflect constitutionally mandated limits on the ability of a state to restrict individual liberties. As a consequence of a BT event, individual citizens might be forced to accept treatment or vaccinations to contain an epidemic. This clearly could create a significant challenge in balancing civil rights.18 The protection of health care workers and first responders will also require planning. Hospitals must consider several issues, such as having a stockpile of antibiotics to treat staff and patients in the case of a BT incident aimed at the hospital, infection control procedures for communicable BT agents, and the ability to decontaminate patients who have been exposed to chemical agents before entering the hospital.20,21 An important issue is the need to treat families of medical care staff to reduce staff need to return home to care for family members. A particularly challenging issue is the need for persons with immunity against smallpox to participate in the investigation and care of suspected or confirmed smallpox cases. The CDC has established teams to investigate potential smallpox outbreaks and has vaccinated those personnel against the disease. However, health care workers and first responders in communities will not have full immunity and will be at risk of contracting smallpox when caring for persons with the disease. The decision to vaccinate these personnel is complicated by of the risk of significant side effects from the vaccine. Another concern is the economic impact of responding to a BT event. Understanding the financial impact is important in developing a comprehensive public health policy. Kaufmann et al22 constructed an economic model comparing the impact of anthrax, tularemia, and Brucella species when released as aerosols in a suburban city.22 The model demonstrated that the economic impact of a BT event ranges from nearly $500 million/ 100,000 persons exposed to $26.2 billion/100,000 persons exposed depending on the agent. The authors concluded that the most important method to reduce these costs was an intact public health structure that could rapidly implement postexposure prophylaxis. Of major importance in responding to a BT event is the ability to rapidly identify the responsible agent. Thus, in the United States, the CDC has made the expansion of its Laboratory Response Network a high priority. Efforts to employ advanced technologies in the development of sensitive and rapid tests for likely BT agents continue. These procedures are being made available to state public health laboratories, which now have the capacity to rapidly diagnose anthrax, plague, and tularemia. Arguably, the most notable deficiency in response to the recent BT events in the United States was the inability to provide timely and accurate information THE AMERICAN JOURNAL OF THE MEDICAL SCIENCES
to the public and to the numerous professionals involved in response activities. Effective communication is a fundamental element of all aspects of public health and is critical for the rapid recognition of, response to, and recovery from public health emergencies. The CDC and state public health agencies are striving to establish a Health Alert Network that would provide essential communication skills and technologies to all jurisdictions in the United States. Major issues to address will include public information, communicating to health professionals, press and public affairs, policy advocacy, and incident command. Public health professionals should establish a good working relationship with the local media, because the media will be critical in disseminating information to the public and to health professionals. References 1. Code of Federal Regulations Title 28 –Judicial Administration, Chapter I–Department of Justice, PART 0, Subpart P–Federal Bureau of Investigation, Section 0.85 General functions. 2. Laqueur W. A history of terrorism. New Brunswick (NJ): Transaction Publishers; 1977. 3. Miller M, Engelberg MS, Broad W. Germs: biological weapons and America’s secret war. New York: Simon and Schuster; 2001. 4. Alibek K, Handelman S. Biohazard. New York: Random House; 1999. 5. Reich W. Origins of terrorism. Baltimore: Woodrow Wilson Center Press; 1998. 6. Conversation with terror. TIME Magazine. 1999 Jan 11. 7. Kolavic SA, Kimura A, Simons SL, et al. An outbreak of Shigella dysenteriae type 2 among laboratory workers due to intentional food contamination. JAMA 1997;278:396 – 8. 8. Osterholm MT, Schwartz J. Living terrors: what America needs to know to survive the coming bioterrorist catastrophe. New York: Delacorte Press; 2000. 9. Jernigan JA, Stephens DS, Ashford DA, et al. Bioterrorism-related inhalational anthrax: the first 10 cases reported in the United States. Emerg Infect Dis 2001;7:933– 44. 10. Gerberding JL, Hughes JM, Koplan JP. Bioterrorism preparedness and response. JAMA 2002;287:898 –9. 11. Biological warfare and terrorism: medical issues and response. In: Medical management of biological casualties handbook (the “blue book”), 4th ed. Ft. Detrick (MD): United States Army Medical Research Institute of Infectious Diseases; 2000. 12. Anonymous. Biological and chemical terrorism: strategic plan for preparedness and response. Recommendations of the CDC Strategic Planning Workgroup. MMWR Recomm Rep 2000;49(RR-4):1–14. 13. Improving local and state response to terrorist incidents involving biological weapons: interim planning guide. Department of Defense, U.S. Army Soldier and Biological Chemical Command, Domestic Preparedness Office, Aberdeen Proving Ground, MD. 2000 Sep 12. Available at: URL: http:// www2.sbccom.army.mil/hld/bwirp/bwirp_interim_planning_ guide_download.htm. 14. Fraser MR, Fisher VS. Elements of effective bioterrorism preparedness: a planning primer for local public health agen-
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cies. Washington DC: National Association of County and City Health Officials; 2001. The public health response to biological and chemical terrorism: Interim planning guidance for state public health officials. Atlanta (GA): Centers for Disease Control and Prevention, July 2001. Available at: URL: http://www.bt.cdc.gov/ Documents/Planning/PlanningGuidance.pdf. The model state emergency health powers act. The Center for Law and the Public’s Health at Georgetown and Johns Hopkins Universities, for the Centers for Disease Control and Prevention. 2001 Oct 23. Available at: URL: http://www. .publichealthlaw.net/MSEHPA/MSEHPA.pdf. Interim smallpox response plan and guidelines. Draft 2.0. Atlanta (GA): Centers for Disease Control and Prevention; 2002 Jan 23. Available at: URL: http://www.bt.cdc.gov/ DocumentsApp/Smallpox/RPG/index.asp. Fidler DP. The malevolent use of microbes and the rule of law: legal challenges presented by bioterrorism. Clin Infect Dis 2001;33:686 –9.
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19. Gostin LO, Burris S, Lazzarini Z. The law and the public’s health: a study of infectious disease law in the United States. Columbia Law Rev 1999;99:59 –128. 20. English JF, Cundiff MY, Malone JD, et al. Bioterrorism readiness plan: a template for healthcare facilities. APIC Bioterrorism Task Force and CDC Hospital Infections Program Bioterrorism Working Group, April 1999. Available at: URL: http://www.cdc.gov/ncidod/hip/Bio/13apr99APICCDCBioterrorism.pdf. 21. California Hospital Bioterrorism Response Planning Guide. Sacramento: California Department of Health Services; 2001. Available at: URL: http://www.dhs.cahwnet. gov/BioTerrorism%20Headline/Revised%20BT%20Response%20master%20document.pdf. 22. Kaufmann AF, Meltzer MI, Schmid GP. The economic impact of a bioterrorist attack: are the prevention and postattack intervention programs justifiable? Emerg Infect Dis 1997;3:83–94.
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