Bioshield, Biosword
by Victor Sidel

Gonna lay down my sword and shield,
Down by the riverside.
I ain’t gonna study war no more.

Gonna shake hands with all the world,
Down by the riverside.
I ain’t gonna study war no more.
—"Down by the Riverside," traditional black spiritual.

It’s easy to understand why the well-known anti-war spiritual calls for laying down the sword, a weapon that can be used to attack as well as to defend. But what is the reason for the call to lay down the shield? There may be a number of reasons: A shield may be less protective than other defensive methods and may give a false sense of protection. A shield may be more costly than other forms of defense. A shield may provoke a pre-emptive attack by a fearful or aggressive enemy. A shield may alienate potential allies who are not protected by the shield. Many shields, from the Maginot Line to National Missile defense, have been viewed as ineffective, expensive, misleading and provocative.

Despite these reasons for eschewing massive investment in improved shields, on July 21, 2004, President George W. Bush signed the Project Bioshield Act of 2004. The legislation had been adopted, virtually unanimously, by the Senate with a vote of 99 to 0 and by the House of Representatives with a vote of 414 to 2. In his comments at the signing ceremony in the White House Rose Garden, surrounded by supportive members of Congress from both parties, the President enumerated three elements of the legislation, which: (1) authorizes $5.6 billion over 10 years for U.S. government purchase and stockpiling of vaccines and drugs against anthrax, smallpox and other diseases; (2) gives the government new authority to expedite research and development on medicines to defend against bioterror; and (3) changes the way the government authorizes and deploys medical defenses in a crisis.

Detailing the first of these elements, the President announced that the Department of Health and Human Services (HHS) had already purchased 75 million doses of a new anthrax vaccine for the Strategic National Stockpile. Under Project Bioshield, he said, HHS plans to acquire “a safer, second generation smallpox vaccine, an antidote to botulinum toxin, and better treatments for exposure to chemical and radiological weapons.” By acting as a buyer for these medical technologies, the government hopes to “ensure that the U.S. drug stockpile remains safe, effective and advanced.” About the second element, he announced the National Institutes of Health had been directed to launch two initiatives — “one to speed the development of new treatments for victims of a biological attack, and another to expedite development of treatments for victims of a radiological or nuclear attack.” About the third element, the U.S. Food and Drug Administration (FDA), the President said, would be able to “permit rapid distribution of promising new drugs and antidotes in the most urgent circumstances. This will allow patients to quickly receive the best available treatments in an emergency.” Secretary Tommy Thompson, the President added, had directed the FDA to prepare guidelines and procedures for implementing this new authority.

Project Bioshield, the President declared, is “a part of a broader strategy to defend the United States against the threat of weapons of mass destruction.” Since September 11, 2001, funding has been increased for the Strategic National Stockpile by a factor of five and funding for biodefense research at NIH by a factor of thirty. The U.S. “has secured enough smallpox vaccine for every American, worked with cities on plans to deliver antibiotics and chemical antidotes in an emergency, improved the safety of the food supply, and deployed advanced environmental detectors under the BioWatch program to provide the earliest possible warning of a biological attack.”

This omnibus legislation, designed to appeal to every constituency and to divert every criticism, clearly has some important features that strengthen medical care and public health in the United States. But the devil, as always, is in the details and the criticisms. These include the ways in which: (1) the threat of biological weapons and of bioterrorism may be purposefully exaggerated; (2) some methods of immunization and treatment may be ineffective and dangerous; (3) development of defensive measures against biological weapons lags behind offensive measures, such as use of alternative organisms or organisms modified by genetic engineering; (4) development of defensive measures may be viewed by a potential adversary as an attempt to develop protection for a nation’s military forces and civilians against organisms that the nation itself might wish to use for offensive purposes; (5) resources may be diverted from other needed public health services; (6) the benefit to public health of “dual use” of anti-bioterrorism funding may be exaggerated; and (7) unilateral defensive measures may discourage multilateral measures for primary prevention of a bioattack.

To examine each of these potential problems in detail:

1) Threats of bioterrorism may be purposefully exaggerated.
At the 1999 annual meeting of the American Public Health Association, a panelist warned the audience that a hypothetical terrorist might, at that moment, be spreading deadly smallpox virus into the air, while in a companion video prepared by the Centers for Disease Control and Prevention (CDC) a shadowy fictional terrorist was shown with a parcel of deadly biological agents that could kill thousands or even millions. In 1998, Secretary of Defense William Cohen held up a five pound bag of sugar on a national television broadcast and declared that if the sugar were anthrax, the organisms could kill half the population of Washington D.C.

Presentations like these are designed to capture attention but contribute little to reasonable assessments of risk. In fact, to date, documented examples of bioterrorism have been rare and have caused relatively few casualties compared with cases of terrorism involving explosives. Only one significant bioterrorism incident has occurred in the United States. In 1984, a religious cult allegedly contaminated several salad bars in Oregon with Salmonella, resulting in numerous cases of gastrointestinal illness but no deaths. Outside the United States the well-financed Japanese religious cult, Aum Shinrikio, used the nerve agent Sarin in two attacks. One killed 7 people in a Tokyo suburb, Matsumoto, in 1994 and the other killed 12 people and injuring a number of others in a Tokyo subway in 1995. The cult also attempted to develop biological weapons but was unsuccessful despite excellent technical capability and years of effort. Although presentations about bioterrorism in the media, at conferences and by government officials repeatedly refer to these episodes as examples, they are the total sum of documented cases.

To make a reasonable estimate of risk of a terrorist attack using biological weapons, it is useful to distinguish between very different types of potential incidents. The most frightening is the use of biological agents in a manner that would cause huge devastation and tens of thousands or even millions of casualties. Weapons using biological agents that could cause catastrophic casualties are extremely difficult to produce and still harder to deploy. Only nation-states with large military, scientific and technical capacity may have the ability to carry out such an attack.

Smaller-scale incidents — similar to those that occurred in Japan or Oregon — could reasonably be considered within the capabilities of organizations or individuals. But attacks must be understood as distinct from catastrophic events. It appears unreasonable to expect that terrorist organizations, in secret and without government support, could develop a capacity that only a limited number of nation-states have had the resources to acquire. Furthermore, weaponization of chemical and biological agents is difficult and dangerous, and would-be weaponizers may be more likely to harm themselves rather than others.
In conclusion, the claims of catastrophic bioterrorism are unnecessarily alarmist and alarmist claims bring their own costs. While the risks of bioterrorism cannot be simply dismissed, neither should they be exaggerated

2) Immunization may be ineffective and dangerous.
Much of the defensive work on biological agents supported by the United States has concentrated on development and stockpiling of drugs to treat infections and of vaccines to prevent them. At first glance, drugs and vaccines appear to offer promise for defense against specific biological agents. If the biological agent or toxin that may be used is known in advance, if it is likely the agent will actually be used, if a vaccine to prevent the infection or toxicity of the agent, or a drug effective in treating it, is known, and if the cost of use of the drug or vaccine in economic or health terms is reasonable, there would appear to be little argument about the defensive benefits of their use.

Major problems occur, however, when the uncertainties involved in such calculations are examined. The precise nature of the biological agent or toxin that will be used, or whether one will be used at all, is unlikely to be known in advance. Even if the agent is known in advance, the efficacy of a drug or vaccine in combating it is rarely known because of the difficulty of adequately testing the drug or vaccine for this purpose and because of the unpredictability of variables such as levels of exposure and the condition of the victims at the time of the attack. The cost of the drug or vaccine in economic terms may be known but the adverse health or collateral effects of use are likely to be largely unknown.

The antibiotics used against anthrax in 2001 were generally effective if treatment began early enough, but other important problems arose. Many people who had no exposure to the organism either had antibiotics prescribed or self-administered them, leading to risk of adverse reactions and to resistance of organisms to these antibiotics.

Two vaccines — one known in the past to be extremely effective and safe and one for which efficacy and safety have been questioned — illustrate the problems posed by a defense strategy based on vaccines.

Smallpox
The threat of smallpox as a biological weapon gained credibility in 1998 when former Soviet biological weapons scientist Ken Alibek alleged that the Soviet Union had produced “scores of tons” of smallpox and plague viruses and had stockpiled “hundreds of tons” of anthrax organisms.(1) He also alleged that smallpox, as well as anthrax, had been weaponized. Other informants reported that the Russians had developed vaccine-resistant strains of smallpox and tested them on prisoners. Alibek's chilling response to a query on what he would use as a biological weapon was, “I'd use anthrax mixed with smallpox.”(2) While questions have been raised about some aspects of Alibek’s credibility, his allegations have clearly had an important influence on biological defense policy.

When the current vaccine against smallpox was used to immunize military personnel and first responders, an unexpected number of serious adverse reactions were seen. Despite efforts to avoid vaccination of those who might be at elevated risk, the CDC reported that there were at least three deaths and at least 71 other adverse events. These deaths and other adverse events might have been justifiable in preparation for a real threat of smallpox or in the midst of a smallpox outbreak, when vaccination might have saved lives. But in the absence of smallpox cases in the world, or any credible basis for expecting an outbreak, they are inexcusable. In light of this experience, in August 2003 a committee of the Institute of Medicine, which had been charged to review the vaccination program, reverted to the position that had been generally accepted before 2002 — that mass, pre-event inoculations were unwarranted. The committee report stated, “in the absence of any current benefit to individual vaccinees and the remote prospect of benefit in the future [as such benefit would be realized only in the event of a smallpox outbreak, and the outbreak occurred in the vaccinee’s region], the balance of benefit to the individual and risk to others [through contact with the vaccinee or through disruption of other public health initiatives] becomes unfavourable… In the absence of other forms of benefit, therefore, offering vaccination to members of the general public is contrary to the basic precepts of public health ethics...”(3)

No credible expert is currently advocating immunization of military forces or civilian populations with vaccinia, the smallpox vaccine. Experts argue only that stockpiles of vaccine against smallpox be prepared, a course of action that the Bioshield Project was created to expidite. Such stockpiles would then be available if an attack with smallpox virus was unleashed. However, these proposals fail to recognize the diversion of resources they require or the fact that unused stockpiles may become outdated and useless. More importantly, they ignore the contention that a genetically-altered smallpox virus might overcome the vaccine, or that merely stockpiling such a vaccine might cause a bioweaponeer to engineer new strains of the virus. They ignore the argument that another nation might be fearful that a potential aggressor nation preparing stockpiles of a vaccine, designed to protect against a disease known to have been eliminated from the earth, might be planning itself to use the organism as a biologic weapon.

In view of the hazards involved in diversionary and expensive preparation for a largely unsubstantiated threat of attack by smallpox virus, the argument that “doing something is better than doing nothing” may actually be counterproductive and hazardous.

Anthrax
In contrast to the anti-smallpox vaccine, which has worked effectively for two centuries to protect those to whom it has been given, the vaccine that was used to protect against inhalation anthrax has not been proven to provide reliable protection against it. Nonetheless, the U.S. Department of Defense used that vaccine for immunization of some 150,000 U.S. troops in the Persian Gulf War and, in 1997, announced that it would be required for all 2.4 million active duty military personnel and reservists. The efficacy, safety and advisability of the program have all been questioned.

There is always the question of whether the efficacy of any vaccine can be assumed, given the possibility that an attacker could either use a different strain or genetically engineer a new one. The anthrax case is particularly poignant since it is known that both of these possibilities already exist. There are several known strains of anthrax, and it is possible that a specific vaccine may not protect against the one that might be used. Furthermore, a particularly troubling use of genetic engineering — the alteration of biological agents to overcome the protection provided by vaccines or antibiotics — has been recognized for some time. In 1997, researchers in Russia disclosed in the British journal Vaccine that they had genetically engineered a strain of vaccine-resistant anthrax that uses genes from Bacillus Cereus.

The available evidence on anthrax underscores the claim that no vaccine against the organism can be claimed to be effective. As the Deputy Director for Science and Public Health of the CDC concluded in 1998: “Although the current anthrax vaccine has been shown to be effective in preventing the cutaneous form of anthrax, CDC is neither aware of definitive data that demonstrates the vaccine's ability to protect against the inhalation form of this disease in humans, nor are we aware of any data relative to the efficacy of this vaccine in humans exposed to genetically-altered Bacillus Anthracis strains.”(4)

The possible risks of inoculating people against anthrax are still largely unknown. The only previous experience with inoculation of large numbers of people with the anthrax vaccine was its use during the Persian Gulf War, but the records of adverse events during this use have never been released. Both the Presidential Advisory Committee on Gulf War Veterans’ Illnesses and the House Committee on Government Reform and Oversight were sharply critical of the failure to maintain adequate records. As the House Committee concluded: “[Department Of Defense] failure to adhere to record-keeping requirements should result in the presumption of service connection for any subsequent illness to service personnel to whom the drug...was administered.”(5)

Furthermore, there were indications that the vaccine being used may have serious defects. Inspections by the U.S. Food and Drug Administration of the supplier, revealed contaminated vaccines, the reuse of outdated vaccines, and the relabeling of lots that originally failed in order to place them into use. These safety problems caused the FDA to halt production in December 1999.

Over 1,500 Vaccine Adverse Event Reporting System (VAERS) reports have been submitted reporting reactions to the vaccine, with at least 200 reactions described as “fatal, life-threatening, or resulting in hospitalization or permanent disability.”(6) Furthermore, passive systems, like VAERS, often result in major under-reporting of adverse reactions, while active reporting systems are likely to provide much more complete and accurate data. In a study at an airbase in Dover, Delaware, for example, it was found that only 20 percent of personnel with probable systemic reactions had actually filed VAERS reports.

A further dangerous consequence of the Bioshield Project is the expansion of research facilities that study potential biological and chemical warfare agents. Known as Biosafety Level-4 (BSL-4) facilities, highly lethal agents such as smallpox and Ebola virus can be stored and studied in them. Until recently, such activities were known to have taken place at a CDC facility in Atlanta and at the U.S. Army's facility at Fort Detrick, Maryland. Under the new program, Plum Island, a Department of Agriculture laboratory on the edge of the New York metropolitan area is being upgraded to BSL-4 and an unknown number of other facilities are also being opened. It is not impossible that these facilities may be used by researchers, with the best of defensive intentions, to attempt to genetically engineer new biowarfare agents in order to evaluate their potential risk and to develop countermeasures.

These facilities pose other serious dangers. They are not immune to accidents and leaks, either at the facilities themselves or during the transport of pathogens. World-wide experiences with presumably fail-safe facilities, such as nuclear power plants, should remind us that accidents can and do happen. Increasing the number of BSL-4 facilities will tend to increase the chance that an accident could occur. The chance of an accident may be remote, but may well be more likely than the threat against which these facilities are designed to prepare.

3) Defensive measures will lag behind offensive measures.
As stated earlier, evidence suggests that genetic engineering has been used to produce modified agents that may be more useful as biological weapons because of their stability, ease of delivery, infectivity, resistance to defensive measures such as immunization, or resistance to treatment once infection or toxicity has occurred. Thus, it is likely that a determined attacker could circumvent the protection provided by immunization or an effective response by drug treatment following an attack. Indeed, it is alleged that the former Soviet Union accomplished this for anthrax and other pathogens by developing strains of organisms that could defeat the American anthrax vaccine or the treatment of diseases caused by biological weapons

4) Defensive measures can imply offensive intent.
Research and development for defenses against biological weaponry are highly ambiguous activities and their pursuit may mislead other nations. The journalist Seymour Hersh reported in 1998 that one of the reasons the U.S. military became concerned about the use of anthrax in the Persian Gulf was the discovery that captured Iraqi soldiers had immunity to the disease.

In the case of Iraq, later evidence showed that U.S. concern that the Iraqi military had weaponized biological agents was justified. But Pentagon preparations to vaccinate U.S. troops might engender precisely the same concerns with respect to U.S. intentions. Actions by the United States to immunize its population, such as Bioshield, might also cause other countries to develop similar defenses, thereby sending ambiguous signals about their own intentions.

While military researchers in a particular country may deny interest in offensive development, given the secrecy surrounding biological warfare activities, it is generally impossible for other states to assess such claims. A nation secretly preparing a stockpile of biological weapons for use in war (whether intended as deterrence, retaliation, or first use) would be likely to prepare vaccines and other defensive measures to protect its own troops and population. Indeed, the reason military leaders are likely to give for the preparation of any form of altered bacilli or viruses, in order to give the appearance of compliance with the Biological Weapons Convention (BWC), is that these organisms are needed for preparation of defenses. However, particularly given the secrecy that shrouds biological warfare activities, it may be impossible for adversaries to determine whether a nation’s defensive efforts are part of preparations for offensive use of biological weapons.

Even if biowarfare research is relatively open, as it would be in the Bioshield Project, other nations may view with suspicion the interest of the U.S. in vaccines or treatment against specific organisms, particularly organisms that are not found in nature or that cause few problems unless purposely spread. Similarly, the present program to build more high-containment facilities suitable for work with lethal pathogens may rekindle an arms race in biological warfare agents.

Just as the U.S. Army supported its requests for appropriation of funds in this area by citing suspicions (and possible exaggerations) of what potential enemies were doing, so the armies of other countries have tried to maximize their resources by casting not-unreasonable suspicions on the activities of the U.S. and its allies. Indeed, it was Dr. Shiro Ishii’s 1930 report that the most powerful Western countries were secretly studying biological weapons, which was almost certainly untrue but unfortunately very plausible, that led to Japan’s embrace of biowarfare research and eventual use of such weapons.(7)

Similarly, the former Soviet Union’s biological weapons program was maintained and expanded after the institution of the Biological Weapons Convention because of suspicions that the United States was continuing research on offensive weapons. The May 2001 public release of a recommendation by a Bush Administration review panel that the United States not accept the draft agreement to strengthen the enforcement of the Biological Weapons Convention has lent new credence to the suspicions that the United States continues work on offensive biological weapons under the cover of defensive research.

5) Resources may be diverted from public health services
Allocation of public funds for social well-being and for public health programs — which are essential to the health of the people of the United States and of the world — should not be a zero-sum game. But even in rich nations like the United States, priority setting for public resource allocation among many urgent needs is required. The funds so far allocated to anti-bioterrorism projects may be small compared to the huge military budget of the United States, but investment of these funds in programs to improve the education, nutrition, housing, and other measures for disease prevention for the world’s peoples would be more effective. Such public health investment is likely to be far more useful for prevention of health consequences if chemical or biological agents were ever used than are the specific secondary prevention measures being proposed in programs such as Bioshield.

The public health burden of the few dramatic and deplorable known incidents of bioterrorism pales in comparison with that of ordinary diseases and accidents. In the United States alone there are an estimated 76 million incidents of food-borne illness each year, with 325,000 hospitalizations and 5,000 deaths.(8) Each year in the United States there are approximately 60,000 chemical spills, leaks and explosions, of which about 8,000 are considered “serious,” with more than 300 deaths.(9)

6) “Dual use” of anti-bioterrorism funding may be exaggerated.
It has been argued that anti-bioterrorism programs will make significantly more money and expertise available for medical and public health infrastructures, a so-called “dual use” of the funding. However, spending patterns so far suggest that the programs will be dominated by anti-bioterrorism spending with little left for meaningful health programs. Of the $10 billion allocated by the U.S. Federal budget for fiscal year 2000 for the anti-terrorism campaign, about $7 billion were allocated to the U.S. Department of Defense. Of the remainder, some $1.5 billion were earmarked specifically for chemical and biological terrorism programs. Some funds would indeed support useful functions like basic surveillance of the incidence of infectious disease and computerization of essential public health data. But these funds do not necessarily represent new public health investments.

7) Unilateral defensive measures may discourage multilateral measures for primary prevention of a bioattack.
Effective prevention of and preparation for the use of biological weapons must start with primary prevention, strengthening the BWC and enforcing it. The United States, in its failure to work with other nations to negotiate and implement a strong inspection regime under the BWC, has undermined its usefulness.

Furthermore, there must be a strong political commitment to abolition of all weapons of mass destruction. If the United States wishes to protect its people against biological weapons, the best method would be to join in negotiating a Nuclear Weapons Convention and, in accordance with it, to dismantle the U.S. nuclear capability. Only then can the United States effectively argue that other nations should give up their weapons of indiscriminate mass destruction, and only then will the world, and the United States and its troops, approach effective protection against biological weapons.

There is an essential role for civil society in this effort. Organizations and individuals must advocate strengthening the BWC and its strict enforcement. Most governments are too constrained — by uneducated electorates or obstinate officials — to exert decisive leadership in this area. Civil society can help provide that leadership. In addition, research organizations, professional societies, and individual scientists should pledge not to engage knowingly in research or teaching that furthers the development and use of biological warfare agents.

If secondary prevention is needed, many public health experts agree that the most effective action would be raising the world population’s overall resistance against serious infectious disease, not just diseases caused intentionally. Such protection requires assuring that the world’s people have adequate nutrition, clothing, shelter, and rest. Use of antibiotics and other treatments of those infected can reduce mortality and morbidity, but are less effective than prevention. Immunization programs will indeed play an important role in this prevention effort. As an example, through immunization programs, it is possible for measles to be entirely eliminated from the world, yet one million people needlessly die annually of this disease. However, efforts to ameliorate the poverty, inadequate nutrition, inadequate housing and inadequate education that underlie much of the world’s preventable disease burden are just as essential for countering disease as immunization. And this is as true for intentionally-caused diseases as it for naturally-caused ones.

Efforts in the United States to prepare drugs and vaccines to combat bioterrorism may suggest to other nations that the United States has little concern for spread of infectious disease to other nations. An international infectious disease control project, rather than the Bioshield Project, would have indicated to people outside the United States that there is concern for the health of people all over the world, and would likely save a great deal more lives.

As part of this effort, industrialized countries should enable developing countries to build capacity for detection, diagnosis and treatment of all disease by providing technical information and needed resources. Article X of the Biological Weapons Convention, encouraging the exchange of information and materials for peaceful purposes, must be strengthened. In particular, nations that are in compliance with the BWC should receive equal treatment with respect to trade in the agents and equipment covered by the BWC. And since some countries appear to be involved in exploring the properties of novel pathogens, another element of the BWC that should be strengthened is the prohibition of development of novel biological agents that do not have a peaceful purpose as their unambiguous justification, even if these activities are promoted for defensive purposes.
Under extraordinary circumstances, such as a credibly imminent attack using known pathogens , short-term use of secondary prevention methods such as barriers, stockpiling of effective antibiotics, or of immunization against the specific pathogen may be justified.

Overall, however, there is little evidence that vaccines, drugs, and associated defense programs can provide effective or ethical solutions to the threat of biological weapons. As Joshua Lederberg, President-Emeritus of Rockefeller University and 1958 Nobel Laureate in Medicine or Physiology, stated in 1998: “There is no technical solution to the problem of biological weapons. It needs an ethical, human and moral solution if it's going to happen at all. There is no other solution.” (10)

Victor Sidel, MD, is Distinguished University Professor of Social Medicine at Montefiore Medical Center and Albert Einstein College of Medicine and Adjunct Professor of Public Health at Cornell Weill Medical Center in New York City. He is a former president of the American Public Health Association, Physicians for Social Responsibility, and International Physicians for the Prevention of Nuclear War.

References
1. Tim Weiner, “Soviet Defector Warns of Biological Weapons,” New York Times. (February 25, 1998),. A1, A8.
2. Committee on Smallpox Vaccination Program Implementation, Board on Health Promotion and Disease Prevention. Review of the Centers for Disease Control and Prevention’s Smallpox Vaccination Program Implementation. Institute of Medicine of the National Academies. Letter Report #4, August 12, 2003.
3. Richard Preston, “The Bioweaponeers,” The New Yorker (March 9, 1998), 52-65.
4. Claire Broome, (Deputy Director for Science and Public Health, Centers for Disease Control and Prevention) Letter to author,. December 14, 1998.
5. Presidential Advisory Committee on Gulf War Veterans' Illnesses. 1997. Special Report, October 31, 1997; Reference to House Committee Report
6. “Anthrax Vaccine Complaints on the Rise,” Hartford Courant (June 2, 2001).
7. John W. Powell, “A Hidden Chapter in History.” Bulletin of the Atomic Scientists 1981; 37(8):45-49; Williams & Wallace
8. P.S. Mead, L. Slutsker, V. Dietz, LF McCaig, JS Bresee, C. Shapiro, PM Griffin and RV Tauxe, “Food-related Illness and Death in the United States,” Emerging Infectious Diseases. Sept-Oct 1999; 5(5):607-650.
9. U.S. Government Printing Office. 1999. House hearings, Internet posting of chemical ‘worst case’ scenarios: a roadmap for terrorists.
10.Richard Preston, “The Bioweaponeers,” The New Yorker (March 9, 1998), 52-65.

Levy B.S., Sidel V.W., eds. Terrorism and Public Health: A Balanced Approach to Strengthening Systems and Protecting People. New York: Oxford University Press, 2003.

Levy B.S., Sidel V.W., eds. War and Public Health. New York: Oxford University Press, 1997. (Paperbound, updated edition, American Public Health Association, Washington, DC, 2000).

Portions of this article are from “Defense against Biological Weapons: Can Imunization and Secondary Prevention Succeed?”, the author’s chapter in Biological Warfare and Disarmament: New Problems/New Perspectives, Ed. Susan Wright, Rowman and Littlefield, Lanham: 2002