How Bioterrorism Works

Unfortunately, a gas mask won't do you much good in the event of a large-scale bioterrorist attack.
Unfortunately, a gas mask won't do you much good in the event of a large-scale bioterrorist attack.
Yoni Zonszein/Getty Images

The attacks of Sept. 11, 2001, alerted the world to the realities of new terrorist threats. Startling images of the Twin Towers falling are indelible and may have overshadowed the events t­hat occurred just a week later. From a public mailbox in New Jersey, letters that contained anthrax spores were mailed to two U.S. senators and several news media outlets. The attack killed five people and infected 18 more. Aside from this tragic loss of life, the attacks furthered the nation's fear and paranoia, and the total cleanup costs exceeded one billion dollars [source: Lengel].

Bioterrorism -- the purposeful release of bacteria, viruses or germs to cause injury, illness or death -- became a reality in the United States. The three ways a terrorist can release biological agents is through air, water or food. These agents are typically very difficult to detect and because the illnesses they cause are usually delayed, it makes bioterrorism a hard crime to investigate. In fact, the anthrax case of 2001 remains unsolved.

Bioterrorism dates back to 1340, when diseased horse corpses were catapulted over castle walls in France. Human bodies infected with plague were also used as ammunition in central Europe during the 14th and 15th centuries. In 1763, a British army general ordered that blankets used on smallpox patients be sent to American Indian tribes. British Revolutionary War troops would also infect themselves with traces of smallpox, rendering themselves immune, in hopes of passing the disease along to the enemy.

During World War I, Germans infected livestock headed for the Allies with anthrax. Even though the attack proved to be unsuccessful, it led to the creation of the Geneva Protocol in 1925. This prohibited the use of biological and chemical agents during wartime, while allowing research and development of these agents to continue. The British and German armies may have dabbled in biological warfare, but the Japanese went full steam ahead in the years that preceded World War II. Hundreds of thousands of Chinese civilians were killed by biological means at the hands of the Japanese army. One of these attacks included dropping paper bags containing plague-infested fleas from low-flying airplanes.

In 1984, the first instance of bioterrorism occurred in the United States. Cult members in rural Oregon sprinkled salmonella on salad bars all around Wasco County, hoping to affect the outcome of a judicial vote. In the end, 750 cases of food poisoning were reported and 45 victims had to be hospitalized. Another cult killed 12 people and injured many more in Tokyo by releasing sarin gas into a crowded subway in 1995.

In this article, we'll learn all about bioterrorism -- the biological agents, the terrorists and the measures in place to combat these evildoers.

Bioterrorism: Agents of Destruction

Emergency crews are decontaminated as police in the Australian state of Victoria conduct a chemical, biological, radiological (CBR) hostage exercise at Caulfield Racecourse in Melbourne, Australia.
Emergency crews are decontaminated as police in the Australian state of Victoria conduct a chemical, biological, radiological (CBR) hostage exercise at Caulfield Racecourse in Melbourne, Australia.
Simon Fergusson/Getty Images

The North Atlantic Treaty Organization (NATO) lists 39 agents that potentially could be used as biological weapons, including viruses, bacteria and toxins. Before you go out and spend a fortune on gas masks, you should know that many of these aren't as likely to be used because of the nature of the agent. In most cases, it would take far too much of any single agent to cause mass amounts of illness or infection. Take ricin, for example -- nearly eight metric tons of this deadly toxin is required to achieve 50 percent lethality over a 62 square mile (100 km) area [source: CDC]. These kinds of statistics make it easier to narrow the list of potential lethal agents that a terrorist might use.

To help categorize and prioritize the study of these agents, the Center for Disease Control (CDC) separates them into three main groups:

  • Category A - easily spread with a high potential for mass casualties, panic and disruption
  • Category B - more difficult to spread with moderate illness rates and low death rates
  • Category C - emerging pathogens that could potentially be easily spread and deadly

Category A agents are the only ones that are suspected as viable bioterrorist threats. This category includes:

  • Anthrax - spores that can infect humans through touch, ingestion or inhalation
  • Botulism - muscle-paralyzing disease caused by a toxic bacterium that's typically ingested through infected food
  • Smallpox - highly contagious, sometimes fatal disease that's only prevented by vaccination
  • Plague - contagious disease caused by bacterium found in rodents and their fleas
  • Tularemia - highly infectious, but not contagious, this rodent disease is also known as "rabbit fever"
  • Viral Hemorrhagic Fevers - a group of diseases caused by viruses such as Ebola and Marbug

Category B agents include salmonella, ricin, cholerae, typhus and undulant fever. These are less of a priority for the CDC because of the unlikelihood they'd be used in a terrorist attack. As for Category A agents, viruses like Ebola are expensive to produce and technically challenging to sustain, in addition to the difficulty of successfully delivering them in large doses. This makes them less likely to be used in a terror attack, but the fact that they can be spread from human to human keeps them in Category A.

Bacteria are much easier to produce than viruses, so they remain the most likely agents for bioterrorism. The World Health Organization (WHO) performed a study in 1970 and found that anthrax and tularemia headed the list of most deadly bacterium with the largest airborne spread. The death rate for untreated anthrax is more than 80 percent; because it can be contracted in three different ways, it's at the top of the list as a potential biological threat.

Smallpox is the one virus exception and ranks alongside anthrax as the most deadly potential threat. Smallpox can also be spread through the air and is able to be manufactured in large doses. The Soviet Union reportedly produced smallpox by the ton during the heyday of the Cold War, and Iraq has experimented with the production of closely related camelpox. Even though smallpox has been eradicated through vaccination, it's believed that no more than 20 percent of the world's population is still immune. Smallpox is also highly contagious, with a single case able to spread to 20 or more people in short order.

In the next section, we'll look into the groups most likely to be involved in bioterrorism and the methods they could use.

Bioterrorism: Organizations and Methods

Indian soldiers shift an injured man to an emergency treatment center during a mock exercise in the event of a Chemical and Biological terror attack, in Kolkata on April 17, 2008.
Indian soldiers shift an injured man to an emergency treatment center during a mock exercise in the event of a Chemical and Biological terror attack, in Kolkata on April 17, 2008.
Deshakalyan Chowdhury/Getty Images

It takes a lot of money and technology to pull off a mass-scale bioterrorist attack, so it remains more of a threat than a reality. In order to launch an effective attack, the organization needs to be extremely well-funded and have access to a great deal of scientific expertise. This means that only large terror groups that may even have state funding could execute an effective mass attack. The group would need several things in order to accomplish this:

  • Access to the unrefined agent
  • Ability to produce large quantities of dry, refined agent
  • Dissemination capabilities

There are only a few organizations in the world with the means to pull something like this off. The Aum Shinrikyo terror group of Japan is well-financed and has attempted to disseminate anthrax and botulism on multiple occasions. So far, it's been unsucc­essful. Iraq was believed to be developing biological weapons to be delivered by scud missiles, but this is classified as biological warfare, not a terrorist attack. The Soviet Union and the United States also experimented with biological weapons before suspending their programs.

Smaller, less sophisticated groups have pulled off minor terrorist attacks using biological agents, but the goal is usually to disrupt society and send people into a panic. The 1980s salmonella poisonings in Oregon are a good example of this kind of biological disruption. Another type of bioterrorist is the lone individual looking to make a social or political statement. Although the case remains unsolved, it's believed that the anthrax attacks of 2001 were the work of a single person or small group of individuals.

The release of an airborne toxin is one of two ways that a terrorist cell might effectively attack a large amount of people at one time. The other is by poisoning their water or food supply. Chances are, if the water or food supply were tainted, it could be contained quickly and the attack wouldn't result in massive casualties. But the civil disruption, panic and financial ramifications would be great -- and most times, that's exactly what terrorists are after.

The effects of the Sept.11 attacks went far beyond the loss of life in New York and Washington, D.C. The airline, insurance, tourism and shipping industries all took a hard hit, which, in turn, had an effect on the overall economy of the United States and world. The direct costs of cleanup and rebuilding in New York alone topped $27 billion, and the projected cumulative loss in national income through the end of 2003 as a result of Sept. 11 came to half a trillion dollars [source: Looney].

In the next section, we'll take a look at what can be done in the event of a bioterrorist attack.

Bioterrorism: After an Attack

Emergency services in chemical protection clothing participate in an anti-chemical and biochemical terror exercise on May 21, 2007 in Seoul, South Korea.
Emergency services in chemical protection clothing participate in an anti-chemical and biochemical terror exercise on May 21, 2007 in Seoul, South Korea.
Chung Sung-Jun/Getty Images

The Center for Disease Control (CDC) is one of the major players in containing a bioterrorist attack and treating the infected individuals. Since anthrax is the most likely agent to be used in a bioterror incident, the CDC has developed a vaccine against it. However, it's available to only "high-risk" individuals such as:

  • Those who work in anthrax research
  • Individuals who work with imported animal hides or furs in areas with insufficient health standards
  • Persons who deal with potentially infected animal products
  • Military personnel in areas with high risk for anthrax exposure

A total of six injections over an 18-month period are required to be fully immunized against anthrax, followed by an annual booster shot. Of course, this is only a vaccine that prevents someone from becoming infected by anthrax and is typically available only to the U.S. military. Treatment of anthrax poisoning is a different subject. Doctors in September 2001 prescribed the antibiotics penicillin, ciprofloxacin and doxycycline to treat the victims of inhalation anthrax. Treatment of this kind of anthrax needs to start early in the progression of symptoms. If it's begun after the symptoms have progressed, then the bacteria may be killed but the toxins will remain in the body.

Additionally, certain strains of anthrax may be resistant to various antibiotics. Lab analysis determines which kind of anthrax is at work and which antibiotic should be used. You can read more about this pathogen in How Anthrax Works.

There are also licensed vaccines against smallpox and an antitoxin treatment available for botulism poisoning, but none of these are available commercially.

The key to handling a bioterrorist attack is to have healthy first responders who can treat victims without becoming sick themselves. After Sept. 11 and the anthrax attacks, the U.S. government sponsored a program to vaccinate 500,000 health care professionals against the smallpox virus. But it was left to each state to head up the program and in the end, less than 40,000 workers were vaccinated [source: Medical News Today]. Workers are usually reluctant to get a vaccination that injects them with a live form of the virus -- especially when there's no actual medical emergency taking place.

If all this makes you feel a little helpless, you'll be glad to know that there are a few things you can do to increase you chances of survival in the event of a bioterrorist attack. We'll take a look at those in the next section.


What Can You Do?

A victim of smallpox
A victim of smallpox
Terrence Spencer/Getty Images

A biological or chemical terror attack can cripple cities with fear and panic, so the most important thing to do is to stay calm. In the event of an attack, the first thing you should do is sit tight and turn on a radio or television to get information. There will be police, emergency coordinators and local government officials available to give information on whether or not you need to evacuate. Every potential terror threat is different, and the emergency coordinator in your area will have specific instructions for evacuation. These directions need to be followed exactly. For instance, if your children are being sheltered at school, you shouldn't try to go get them. If you do evacuate, bring any medications you'll need, and if you can, call a friend or relative and let him or her know where you're headed. The same emergency coordinators who gave evacuation orders will also let you know when it's safe to return home.

Aside from evacuation, there are two things you should be well-acquainted with in the case of a chemical attack: decontamination and sheltering in place procedures. Your emergency coordinator or local police force will let you know if you need to decontaminate yourself. There are three important steps to decontamination:

  • Quickly remove your clothes: Cut off anything that needs to be pulled over your face.
  • Wash yourself thoroughly: Use large amounts of soap and water. If your eyes are burning, rinse with cool water for 10 to 15 minutes. If you wear contact lenses, take them out and don't put them back in.
  • Dispose of your clothes: Put them in a plastic bag and avoid touching the contaminated areas by using rubber gloves or tongs. Seal the bag, and then put it inside another bag. Leave the bag alone to be disposed of by a professional.

Sometimes, if the air outside your home is laced with a chemical or biological agent, evacuation can be more dangerous than staying put. This is when your local police will advise you to shelter in place. Sheltering should happen in a home or building whenever possible -- your car isn't airtight enough. Follow these steps to shelter in place:

  • Turn off your HVAC system and any other fans
  • Close and lock all windows and doors in the house as well as the fireplace damper
  • Choose a room with a water supply and as few windows and doors as possible for your shelter (A master bedroom with a bath is an ideal choice.)
  • Go as high in your home or building as possible
  • Turn on a radio or TV and keep a telephone close by
  • Do not drink tap water
  • Tape plastic over the windows, doors and vents
  • Only come out when the police or emergency personnel says it's safe

In the next section, we'll look at what programs are in place to help prevent a bioterrorism attack.

Bioterrorism Countermeasures: The FDA

The Anthrax test kit, produced by Tetracore, Inc., provides an on-site screening of biological threats such as Anthrax, Ricin and Botulinum Toxin.
The Anthrax test kit, produced by Tetracore, Inc., provides an on-site screening of biological threats such as Anthrax, Ricin and Botulinum Toxin.
Sandy Schaeffer/Getty Images

The Food and Drug Administration (FDA) plays a vital role in the efforts to counter a bioterrorist attack with five broad strategies:

  • Awareness
  • Prevention
  • Preparedness
  • Response
  • Recovery

The FDA set up the Office of Crisis Management (OCM) to help implement these efforts. The OCM is responsible for maintaining vigilance 24 hours a day, seven days a week, and coordinates the emergency response efforts for the five FDA centers around the country in the event of an attack. It's also responsible for heading up emergency training drills, securing the FDA buildings and educating employees in crisis management methods.

The FDA has always been responsible for the regulation of products for public consumption -- including food, drugs, medicine, medical devices, animal feed and cosmetics. In this age of heightened security threat, it's now responsible for safeguarding these products as well. The FDA is working hard to develop medical countermeasures such as vaccines and devices that can prevent, diagnose and treat bioterror illnesses.

The key to an effective response in the event of an emergency is coordinating the efforts of many different agencies. After Sept. 11 and the anthrax attack, the FDA joined forces with the Center for Disease Control (CDC) and the Department of Defense (DoD) as well as with foreign government agencies in order to ensure that medical supplies were available and at the ready. They developed the Strategic National Stockpile (SNS) -- a large cache of antibiotics, antitoxins, medical supplies, vaccines and surgical supplies. The FDA packaged emergency drug parcels called push packs which can be sent to any destination in the United States within 12 hours.

One of the methods a terrorist might use is to poison livestock or animal feed. The FDA's Center for Veterinary Medicine (CVM) is working with Iowa State University to establish a database that incorporates all veterinary labs across the country. This would be used to improve response time for animal or feed related terrorism. The network also establishes the veterinary centers that have testing capabilities for feed and animal tissue.

The FDA has a lot of experience dealing with accidental poisoning and natural food and feed contamination. Managing these accidents has helped them to prepare for the prospect of a purposeful attack. In addition to this experience, new safeguards have been put in place to help guard the U.S. food supply in the following areas:

  • Prevention and surveillance -- the FDA issued guidance for food processors, producers, importers and transporters. It worked with the United States Dairy Association (USDA) to establish the Food Emergency Response Network, a web of laboratories capable of rapid testing.
  • Protecting imports -- improved efforts to protect the 6 million food shipments that enter the United States each year. More than 600 new food inspectors have been hired to help accomplish this goal. The FDA has also established six times as many inspection exams for imported food.

Tainted blood is another way that a terrorist might implement an attack, and the FDA is partially responsible for protecting this supply. They've worked with the American Association of Blood Banks (AABB) to write and distribute handbooks on emergency and disaster related coordination. This handbook covers everything relating to blood -- from how to handle an influx of donors in a disaster to the proper screening and testing methods to ensure that donated blood and the existing supply remains untainted.

Click ahead to the next page to learn about the two government projects in place to help protect citizens of the United States from a bioterrorist attack.

Countermeasures: Bio-Watch and Project Bioshield

Members of Congress are pleased when President Bush autographs the "Project Bioshield" legislation.
Members of Congress are pleased when President Bush autographs the "Project Bioshield" legislation.
Stephen Jaffee/Getty Images

As a result of the terror attacks on New York and Washington, D.C., President George W. Bush implemented two different programs to help safeguard the citizens of the United States: Bio-Watch and Project Bioshield.

Bio-Watch was born shortly after the anthrax mailings of September 2001. It's funded and overseen by the Department of Homeland Security (DHS), but because of the sensitive nature of the program, there aren't too many details available to the general public. We do know that it's an early warning system that detects airborne pathogens in select cities across the United States. Media reports suggest that there are nearly 30 cities currently using Bio-Watch and as many as 120 cities are in line for future implementation.

Bio-Watch monitors are reportedly placed on top of selected buildings in target cities to collect air samples, which are transported to laboratories on a daily basis for analysis. The symptoms of many of the illnesses from bioterror pathogens aren't apparent for several days and can even be mistaken for common illnesses like cold and flu. The early detection that Bio-Watch provides could make a big difference in emergency response time.

There are three main elements to Bio-Watch, and each is coordinated by a different government agency:

  • Sampling -- maintained by the Environmental Protection Agency (EPA)
  • Analysis -- coordinated by the CDC
  • Response -- implemented by local jurisdictions under the guidance of the Federal Bureau of Investigation (FBI)

We know that anthrax and smallpox are on the list of pathogens that Bio-Watch detects, but the others are closely guarded by the DHS. So far, there's only been a single positive detection that we know about  -- bacteria that causes tularemia was found in Houston, Texas, in 2003. Detection was reported on three consecutive days, followed by negative results on the following days. Precautionary measures were taken by local law enforcement officials, but the incident never resulted in any illness or arrests.

The effectiveness of Bio-Watch has been under fire since its implementation. One reason is that Bio-Watch detects only outdoor pathogens. Most of the biological terror attacks around the world thus far have been indoor incidents -- subways and offices. Another concern is that the turnaround on samples is 12 to 48 hours after an attack has taken place, which isn't exactly ideal. Others complain that it's not cost-effective for the results it achieves. Reports place installation costs at $1 million, with another million for annual operation and upkeep. In February 2008, the DHS requested a $34.5 million increase in funding to design and implement the next generation of Bio-Watch.

Project Bioshield is another program that President Bush put into action after Sept.11. Bioshield provides the government with the resources it needs to develop, acquire and stockpile medical countermeasures against bioterrorism. The program allows for further research, development and acquisition of next generation vaccines by granting $5.6 billion over the next decade. It also established the Emergency Use Authorization (EUA), which makes sure that these vaccines and medicines are accessible following a Declaration of Emergency by the Secretary of Health and Human Services.

For more information on terrorism, please put on your gas mask and visit the links on the following page.

Related HowStuffWorks Articles

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