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Bioterrorism is the use of a biological weapon against a civilian population. As with any form of terrorism, its purposes include the undermining of morale, creating chaos, or achieving political goals. Biological weapons use microorganisms and toxins to produce disease and death in humans, livestock, and crops.

Biological, chemical, and nuclear weapons can all be used to achieve similar destructive goals, but unlike chemical and nuclear technologies that are expensive to create, biological weapons are relatively inexpensive. They are easy to transport and resist detection by standard security systems. In general, chemical weapons act acutely, causing illness in minutes to hours at the scene of release. For example, the release of Sarin gas by the religious sect Aum Shinrikyo in the Tokyo subway in 1995 killed 12 and hospitalized 5,000 people. In contrast, the damage from biological weapons may not become evident until weeks after an attack. If the pathogenic (disease causing) agent is transmissible, a bioterrorist attack could eventually kill thousands over a much larger area than the initial area of attack.

Bioterrorism can also be enigmatic, destructive, and costly even when targeted at a relatively few number of individuals. Starting in September 2001, bioterrorist attacks with anthrax causing bacteria distributed through the mail, targeted only a few U.S. government leaders, media representatives, and seemingly random private citizens. As of May 2003, these attacks remain unsolved. Regardless, in addition to the tragic deaths of five people, the terrorist attacks cost the United States millions of dollars and caused widespread concern. These attacks also exemplified the fact that bioterrorism can also strike at the political and economic infrastructure of a targeted country.

Although the deliberate production and stockpiling of biological weapons is prohibited by the 1972 Biological Weapons Convention (BWC)—the United States stopping formal weapons programs in 1969—unintended byproducts or deliberate misuse of emerging technologies offer potential bioterrorists opportunities to prepare or refine biogenic weapons. Genetic engineering technologies can be used to produce a wide variety of bioweapons including organisms that produce toxins or that are more weaponizable because they are easier to aerosolize (suspend as droplets in the air). More conventional laboratory technologies can also produce organisms resistant to antibiotics, routine vaccines, and therapeutics. Both technologies can produce organisms that cannot be detected by antibody-based sensor systems.

Among the most serious of protential bioterrorist weapons are those that use smallpox (caused by the Variola virus), anthrax (caused by Bacillus anthracis), and plague (caused by Yersinia pestis). During naturally occurring epidemics throughout the ages, these organisms have killed significant portions of afflicted populations. With the advent of vaccines and antibiotics, few U.S. physicians now have the experience to readily recognize these diseases, any of which could cause catastrophic numbers of deaths.

Although the last case of smallpox was reported in Somalia in 1977, experts suspect that smallpox viruses may be in the biowarfare laboratories of many nations around the world. At present, only two facilities—one in the United States and one in Russia—are authorized to store the virus. As recently as 1992, United States intelligence agencies learned that Russia had the ability to launch missiles containing weapons-grade smallpox at major cities in the U.S. A number of terrorist organizations—including the radical Islamist Al Qaeda terrorist organization—actively seek the acquisition of state-sponsored research into weapons technology and pathogens.

There are many reasons behind the spread of biowarfare technology. Prominent among them are economic incentives; some governments may resort to selling bits of scientific information that can be pieced together by the buyer to create biological weapons. In addition, scientists in politically repressive or unstable countries may be forced to participate in research that eventually ends up in the hands of terrorists.

A biological weapon may ultimately prove more powerful than a conventional weapon because it's effects can be far-reaching and uncontrollable. In 1979, after an accident involving B. anthracis in the Soviet Union, doctors reported civilians dying of anthrax pneumonia (i.e., inhalation anthrax). Death from anthrax pneumonia is usually swift. The bacilli multiply rapidly and produce a toxin that causes breathing to stop. While antibiotics can combat this bacillus, supplies adequate to meet the treatment needs following an attack on a large urban population would need to be delivered and distributed within 24 to 48 hours of exposure. The National Pharmaceutical Stockpile Program (NPS) is designed to enable such a response to a bioterrorist attack.

Preparing a strategy to defend against these types of organisms, whether in a natural or genetically modified state, is difficult. Some of the strategies include the use of bacterial RNA based on structural templates to identify pathogens; increased abilities for rapid genetic identification of microorganisms; developing a database of virtual pathogenic molecules; and development of antibacterial molecules that attach to pathogens but do not harm humans or animals. Each of these is an attempt to increase—and make more flexible—identification capabilities.

Researchers are also working to counter potential attacks using several innovative technological strategies. For example, promising research with biorobots or microchipmechanized insects with computerized artificial systems that mimic biological processes such as neural networks, and can test responses to substances of biological or chemical origin. These insects can, in a single operation, process DNA, screen blood samples, scan for disease genes, and monitor genetic cell activity. The robotics program of the Defense Advanced Research Project (DARPA) works to rapidly identify bio-responses to pathogens, and for designs to effectively and rapidly treat them.

Biosensor technology is the driving force in the development of biochips for detection of biological and chemical contaminants. Bees, beetles, and other insects outfitted with sensors are used to collect real-time information about the presence of toxins or similar threats. Using fiber optics or electrochemical devices, biosensors have detected microorganisms in chemicals and foods, and off the promise of rapid identification of biogenic agents following a bioterrorist attack. The early accurate identification of biogenic agents is critical to implementing effective response and treatment protocols.

To combat biological agents, bioindustries are developing a wide range of antibiotics and vaccines. In addition, advances in bioinformatics (i.e., the computerization of information acquired during, for example, genetic screening) also increases flexibility in the development of effective counters to biogenic weapons.

In addition to detecting and neutralizing attempts to weaponize biogenic agents (i.e., attempts to develop bombs or other instruments that could effectively disburse a bacterium or virus), the major problem in developing effective counter strategies to bioterrorist attacks Cipro is used to treat anthrax and as of late 2002 was produced in limited supply. © FRI/Corbis Sygma. Reproduced by permission. involves the breadth of organisms used in biological warfare. For example, researchers are analyzing many pathogens in an effort to identify common genetic and cellular components. One strategy is to look for common areas or vulnerabilities in specific sites of DNA, RNA, or proteins. Regardless whether the pathogens evolve naturally or are engineered, the identification of common traits will assist in developing counter measures (i.e., specific vaccines or antibiotics).



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Tucker, Jonathan. Toxic Terror: Assessing Terrorist Use of Chemical and Biological Weapons. Cambridge, MA: MIT Press, 2002.


Glass, Thomas, and Monica Schoch-Spana. "Bioterrorism and the People: How to Vaccinate a City against Panic" Clinical Infectious Diseases (January 15, 2002): 34 (2).

Inglesby, Thomas V, et. Al. "Anthrax as a Biological Weapon, 2002-Updated Recommendations for Management " Journal of the American Medical Association (May 1,2002):


United States Food and Drug Administration Center for Food Safety and Applied Nutrition. "Food Safety and Terror
ism" [cited February 5, 2003]. <http://www.cfsan.fda.gov/~dms/fsterr.html>.


Unites States Department of Homeland Security. "President Discusses Measures to Protect Homeland from Bioterrorism" [cited February, 5, 2003]. <http://www.whitehouse.gov/homeland/>.

Brian Hoyle

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