Module 1:


1. What is a biological weapon?

  • A biological weapon is a system that disseminates microorganisms or toxins to sicken or kill people, animals, or plants. It generally consists of two parts:
    1. A weaponized causative agent
    2. A delivery system
  • The causative agent can be microorganisms that causes disease, such as bacteria, viruses, or fungi, or chemicals derived from living organisms such as prions and toxins.
  • Delivery systems range from very simple devices (e.g., an envelope, brushes, basic injection systems, or food and water contamination) to sophisticated devices (e.g., aerosol spray devices, bombs, and missiles).


1. Bacteria

Bacteria are unicellular organisms that are the causative agents of numerous diseases. They come in many different shapes and vary considerably in infectivity and lethality.

Examples: Bacillus anthracis (Anthrax), Yersina pestis (Plague), Francisella tularensis (Tularemia)

Photo: Yersinia Pestis (Plague) | Photo Credit:


2. Viruses

Viruses are bundles of genetic material carried in shells called viral coats or capsids. Viruses cannot reproduce on their own, and thus must inject their genetic material into host cells and then take over their reproductive machinery to make new virus particles.

Examples: Variola (smallpox), Ebolavirus (Ebola), Flavivirus (Yellow Fever)

Photo: Ebolavirus (Ebola) | Photo Credit: CDC Global via WikiMedia Commons

Valley Fever

3. Fungi

Mushrooms, molds, and yeasts are all examples of fungi. Roughly 300 species of fungi cause disease in humans, usually by entering through the skin, hair, lungs, gastrointestinal tract, or bloodstream. Fungi can also cause disease in animals or crops.

Examples: Coccidioides (Valley Fever), Claviceps purpurea (Ergot)

Photo: Coccidiodes (Valley Fever) | Photo Credit: CDC / Lucille Georg

Creutzfeldt Jakob Disease

4. Prions

Prions are misfolded proteins that interfere with the function of otherwise healthy proteins in organisms. They cause neurodegenerative diseases, such as mad cow disease in cattle or variant Cruetzfeldt-Jakob Disease in humans.

Examples: Spongiform Encephalopathy (Mad cow disease), Variant Cruetzfeldt-Jakob Disease

Photo: Variant Creutzfeldt-Jakob Disease | Photo Credit: Centers for Disease Control and Prevention via WikiMedia Commons

Clostridium Bacteria

5. Toxins

Toxins are poisonous chemicals produced by living cells or organisms. Toxins can also be produced synthetically. Toxins can be injected, inhaled, or ingested.

Examples: Botulinum toxin, Ricin, Saxitoxin

Photo: Clostridium Bacteria | Photo Credit: CDC / Dr. Holdeman

2. Have biological weapons ever been used?

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3. Which countries have or at one time had biological weapons?

Bioweapon Facility 731

1. Japan

  • From 1932 to 1945, maintained robust BW program codenamed Unit 731
  • Tested cholera, anthrax, plague, dysentery, glanders, hemorrhagic fever, typhoid, and paratyphoid on Chinese civilians and Allied prisoners of war
  • Conducted extensive BW operations, including spreading plague-infected fleas, among Chinese soldiers and civilian populations

Source: James W. Martin, George W. Christopher, and Edward M. Eitzen, “History of Biological Weapons: From Poisoned Darts to Intentional Epidemics,” in Medical Aspects of Biological Warfare, ed. Zygmunt F. Dembek, Falls Church, VA: Office of the Surgeon General, 2007.

Photo: Building on the site of a Unit 731 facility in Manchuria | Photo Credit: Wikimedia Commons

Bioweapon Facility 731

1. Japan Cont.

  • Enormous death tolls: tens of thousands killed in Unit 731 human experimentation alone, perhaps hundreds of thousands killed in BW operations during war with China
  • Dismantled the program after WWII and ratified the Biological and Toxin Weapons Convention (BTWC), June 8, 1982

Source: Harris, Sheldon H. 2002. Factories of Death: Japanese Biological Warfare, 1932-1945, and the American Cover-Up, New York, London: Routledge.

Photo: Building on the site of a Unit 731 facility in Manchuria | Photo Credit: Wikimedia Commons

Kurt Blome

2. Germany

  • Conducted research into anti-livestock and anti-crop pathogens during WWI
  • Used biological sabotage against draft animals in Allied and neutral countries during WWI
  • During WWII, conducted limited research into biological weapons, but no extensive program
  • Both West Germany and East Germany ratified the BTWC in 1972

Source: Mark Wheelis, Lajos Rózsa, and Malcolm Dando, “Deadly Cultures: Biological Weapons Since 1945,” (Harvard University Press) 2006, pg. 9-10.

Photo: Kurt Blome, head Nazi Germany’s biological warfare research program, as a defendant at the Nuremburg Trials | Photo Credit: United States Holocaust Memorial Museum, via Wikimedia Commons

E120 Biological Bomblet Cutaway

3. United States

  • Began research into the ricin toxin during WWI
  • During WWII and the early Cold War, developed robust BW program; researched anthrax, brucellosis, botulinum toxin, Q fever, rice blast, tularemia, wheat rust, and Venezuelan equine encephalitis virus
  • Delivery systems included bomblets & spray tanks; researched insects as vectors
  • Terminated offensive BW in 1969 & ratified the BTWC on March 26, 1975

Source: Jeffrey K. Smart, “Chapter 2: History of Chemical and Biological Warfare: an American Perspective,” in Russ Zajtchuk and Ronald Bellamey, eds., Medical Aspects of Chemical and Biological Warfare, (Washington DC: TMM Publications, 1997) pp. 21-22,

Photo: E120 Biological bomblet cutaway | Photo Credit: U.S Customs Service via Wikimedia Commons

A license plate from the Suffield Research Facility

4. Canada

  • Researched anthrax, rinderpest, and allegedly tularemia during World War II
  • Aided biological weapons research programs in the United States and Great Britain
  • Ratified the BTWC on September 18, 1972

Source: John Bryden, “Deadly Allies: Canada’s Secret War 1937-1947″ (McClelland and Stewart) 1989.

Photo: A license plate from the Suffield Research Facility in Alberta, once the site of biological weapons research | Photo Credit: CJerry “Woody” via Flickr

Abu Ghurayab

5. Iraq

  • Began pursuing BW program in 1985, producing anthrax, wheat cover smut, aflatoxin, botulinum toxin, and ricin
  • Ratified the BTWC on June 19, 1991 after defeat in the Gulf War
  • Developed bombs, artillery shells, sprayers, and Scud missiles for delivery
  • Despite ratifying the BTWC, maintained its key BW production facility at al-Hakam until 1996

Sources: “The Biological Weapons Programme,” Compendium of Iraq’s Proscribed Weapons Programmes in the Chemical, Biological and Missile Areas (New York, NY: United Nations, 2007) pp. 766-791,; Resolution 687, UN Document S/RES/687 (1991), Paragraph 7, April 8, 1991,

Photo: Iraq claimed Abu Ghurayab to be a baby milk factory. The U.S. destroyed it, mistaking it for a BW facility. (CIA, 2007) | Photo Credit: DoD, via Wikimedia Commons

Gruinard Island

6. United Kingdom

  • Began BW program during WWII, weaponizing anthrax and researching botulinum toxin, plague, and typhoid
  • Developed anti-livestock and anti-personnel anthrax bombs during WWII
  • After the UK tested its first atomic bomb in 1952, importance of BW diminished
  • Ratified the BTWC on March 26, 1975

Source: Milton Leitenberg, “Biological Weapons in the Twentieth Century: A Review and Analysis,” 7th International Symposium on Protection against Chemical and Biological Warfare, Stockholm, Sweden, June 2001,

Photo: Gruinard Island, site of a 1942 anthrax test by the United Kingdom that contaminated the land for more than fifty years | Photo Credit: Pere Ubu via Flickr

Stepnagorsk Scientific Experimental and Production Base

7. Soviet Union

  • Launched full military biological weapons program in 1928, retained most extensive BW program in history
  • Ratified BTWC on March 26, 1975, however, expanded BW program significantly around same time
  • Conducted research on anti-personnel, anti-livestock and anti-plant agents, including anthrax, glanders, Marburg, plague, Q fever, smallpox, tularemia, and Venezuelan equine encephalitis

Source: Raymond A. Zilinkas, The Soviet Biological Weapons Program: A History, (Cambridge, MA: Harvard University Press, 2012).

Photo: Stepnagorsk Scientific Experimental and Production Base certified large-scale production and weaponization of biological agents, National Reconnaissance Office. | Photo Credit: National Reconnaissance Office via Wikimedia Commons

Stepnagorsk Scientific Experimental and Production Base

7. Soviet Union Cont.

  • Delivery systems included bomblets, artillery rockets, and sprayers
  • Genetically engineered viruses and bacteria for increased lethality and resistance to countermeasures
  • Terminated program after collapse of USSR in the 1990s
  • Concerns persist about Russia’s residual capacity to produce biological weapons

Source: Raymond A. Zilinkas, The Soviet Biological Weapons Program: A History, (Cambridge, MA: Harvard University Press, 2012).

Photo: Stepnagorsk Scientific Experimental and Production Base certified large-scale production and weaponization of biological agents, National Reconnaissance Office. | Photo Credit: National Reconnaissance Office, via Wikimedia Commons

The Pasteur Institute

8. France

  • Began BW program in 1921 due to concerns about German offensive biological weapons capabilities
  • Conducted research on anthrax, cholera, salmonella, rinderpest, botulinum toxin, and ricin
  • Developed various bombs and sprayers
  • Acceded to BTWC on September 27, 1984

Source: Olivier Lepick, “French activities related to biological warfare, 1919-45,” Biological and Toxin Weapons: Research, Development and Use from the Middle Ages to 1945, eds. Erhard Geissler and John Ellis van Courtland Mood (New York: Stockholm International Peace Research Institute, 1999), pp. 70, 78, 82- 90.

Photo: The Pasteur Institute, an important biological research center, 1908 | Photo Credit: Wikimedia Commons

South Africa Roodeplaat

9. South Africa

  • Began covert BW program in 1981, codenamed Project Coast
  • Conducted research into anthrax and botulinum toxin for assassinations
  • Ratified the BTWC on November 3, 1975, but continued to pursue a BW capacity
  • Dismantled program in 1993 after collapse of apartheid regime

Source: “Truth and Reconciliation Commission of South Africa Report,” Vol. 2, October 29, 1998, p. 514.

Photo: Monkey cages at Roodeplaat Research Laboratories, a front organization for the South African biological weapons program.
Photo Credit: Nelson Mandela Foundation

4. What is the difference between offensive biological weapons programs and biodefense?

The Biological and Toxins Weapons Convention (BTWC) prohibits its members from undertaking offensive biological weapons activities but permits research and the development of antidotes and other defenses against biological weapons. It can be difficult to delineate the boundary between offensive and defensive programs because offensive and defensive research often employ the same equipment, technologies and techniques. The following scenarios illustrate the difficulty of categorizing biological programs as offensive or defensive.

Scenario 1: Scientists genetically engineer a new and deadly strain of a common BW agent.

Why it could be biological warfare:
Past BW programs have tried to re-engineer existing pathogens to leave their adversaries without the usual defenses against them.
Why it could be biodefense:
A scientist working on antiviral drug development might be trying to understand how, and how fast, the virus could evolve to resist treatment.

Scenario 2: A disease outbreak occurs near a military base known to work with biological agents.

Why it could be biological warfare:
Leaks from biological weapons research and production can lead to disastrous outbreaks. Notably, the 1979 anthrax leak in Sverdlovsk, USSR resulted in approximately 100 deaths.
Why it could be biodefense:
Defensive biological programs also use agents which could lead to an outbreak if mishandled. Additionally, some BW agents like Bacillus anthracis exist in nature and outbreaks may have natural causes.

Scenario 3: Military units conduct tests of aerosol dispersal agents at a remote, outdoor test facility.

Why it could be biological warfare:
A country planning a large-scale biological attack would need to test aerosol technologies to successfully disperse biological warfare agents.
Why it could be biodefense:
Aerosol tests are necessary for biological defense, to test aerosol detection systems and to train troops on the use of biological disinfectants.

Scenario 4: The military initiates a campaign to inoculate its troops against anthrax.

Why it could be biological warfare:
The military may be trying to ensure that its forces are protected from blowback of agents that it may use on the battlefield.
Why it could be biodefense:
The military may just be trying to ensure that its forces are prepared for anything that the enemy may use against them.

Scenario 5: Military medical personnel seek to obtain deadly viral strains from abroad.

Why it could be biological warfare:
A state seeking to develop a biological weapons program may attempt to procure biological agents elsewhere, particularly if it lacks an advanced biomedical industry.
Why it could be biodefense:
The military may be participating in public health or biodefense initiatives with the help of a foreign entity.

Photo Credit
Header Image: Electron micrograph of Escherichia coli. Source: WikiMedia Commons.