History of biological warfare

Before the 20th century, the use of biological agents took three major forms:

• Deliberate contamination of food and water with poisonous or contagious material
• Use of microbes, biological toxins, animals, or plants (living or dead) in a weapon system
• Use of biologically inoculated fabrics and persons

In the 20th century, sophisticated bacteriological and virological techniques allowed the production of significant stockpiles of weaponized bio-agents:

• Bacterial agents: Anthrax, Brucella, Tularemia, etc.
• Viral agents: Smallpox, Viral hemorrhagic fevers, etc.
• Toxins: Botulinum, Ricin, etc.