By Barry C. Fox, M.D., University of Wisconsin
September 11, 2001, changed America and Americans. The knowledge that we were vulnerable to attacks by terrorists, even though we were protected by vast oceans, was a terrible realization. Seven days later, a new type of terrorism, a bioterrorist attack hit the US in the form of anthrax in five envelopes sent through the United States Postal System.

Anthrax Postal Attack
You may remember the first case, which occurred in Florida and resulted in the first death from anthrax. Letters were sent to American Media, NBC, ABC, CBS, and a senator’s office at the State Department. This attack resulted in 22 cases of anthrax, with five deaths due to inhalation of bacterial spores.
Besides the deaths, there was mass chaos in the Washington, DC, area due to concern about the postal service and the death of two workers. Nineteen thousand tests were performed, and 33,000 individuals were placed on prophylactic antibiotics. Time-consuming and costly environmental surveys of post offices and mailrooms were performed, and mail service was significantly interrupted. Decontamination of one building alone cost $23 million.
Experts say that it’s not a maybe anymore; bioterrorism will happen—meaning the intentional release of viruses, bacteria, or other germs. These germs have the potential to devastate our food supply, infest our water, contaminate the air, and ultimately sicken or kill people.
This is a transcript from the video series An Introduction to Infectious Diseases. Watch it now Wondrium.
Bioterrorist Attacks in the Middle Ages
Although not well documented, there are a few stories of early bioterrorism. As early as the 14th and 15th centuries, dead, diseased bodies of infected humans or animals were flung at the enemy with catapults—some of the first trials of bioweapons. One instance took place in Caffa, a city in Ukraine, which was under attack. The Tartars turned their misfortune of a plague epidemic into a new form of attack weapon.

There are also several accounts of attempting to spread smallpox to the enemy via tainted blankets, one of which took place during the conquest of the Incas in Peru and another against Native American Indians. Believe it or not, in 1675, there was an early Bioweapons Treaty. The Holy Roman Empire and the French agreed not to use poisonous bullets against one another.
Other agents over the years included the saliva of rabid dogs and even containers of poisonous snakes. Those of you who are Sherlock Holmes fans might be amused to know about a fictional account of bioterrorism. In The Adventure of the Dying Detective, Holmes investigates a murder where he suspected a bioweapon had been used. All indications pointed to plague as being the murder weapon in question.
Learn more about the steps CDC takes to protect the public.
Modern Bioterrorism
Let’s explore modern threats of bioterrorism and the agents that might be used in an attack. There have been efforts in the 20th century to curtail the use of bioweapons. For example, in 1925, the Geneva Protocol was established, prohibiting the use of chemicals and biological agents, but not the research and development of them.
During the Cold War, both Russia and the United States developed weapons of bioterrorism. And during the ’50s and ’60s in the U.S., open-air tests were performed with what was thought to be a harmless bacteria named Serratia Marcescens. The U.S. government wanted to know what would happen if a bioweapon was planted in a subway or was dropped from a plane.
In an actual trial in San Francisco, it was disturbing to find that almost all of the 800,000 residents showed traces of Serratia. In another test, a light bulb filled with harmless bacteria was dropped on the subway tracks in New York City. The organism spread throughout the subway system within 20 minutes.
By the late 1960s, the United States had a large arsenal of different pathogens stored up in the form of bacteria, fungi, and toxins. However, in 1969, President Nixon terminated the offensive biological warfare program. He ordered the destruction of stockpiled weapons. After that, the U.S. research focused on defensive, rather than offensive measures.
Learn more about emerging and reemerging diseases.
How the Soviets Messed Up
In 1972, the U.S. and more than 100 nations signed the Biological and Toxin Weapons Convention, or BWC, the world’s first treaty banning an entire class of weapons. More specifically, the treaty banned the research, development, production, stockpiling, or acquisition of biological weapons, as well as the means to deliver them.

But in 1979, a powdered form of anthrax was accidentally released from a Soviet bioweapons facility in Russia, killing 70 people. This facility was able to produce tons of the toxin. Although the Russians blamed contaminated meat for the deaths to cover up the accident, in 1992, a U.S. team visited the site. They found evidence in the lungs of victims—that many died from inhalation anthrax—a serious violation of the BWC treaty.
Through several defectors from the Soviet Union, the United States gained knowledge of the enormous size of the Soviet’s bioweapons program. This allegedly included a genetically altered super plague, antibiotic-resistant anthrax, and long-range missiles to spread disease.
Evidently, the Soviet program had facilities with thousands of scientists. In the 1980s and 1990s, many of these scientists became free agents—with dangerous knowledge for sale. Today, we think there are bioweapons in at least 12 countries, spurring the need for preparedness by medical and public health organizations.
Common Questions about a Brief History of Bioterrorist Attacks
In the aftermath of the anthrax bioterrorist attack, nearly 20,000 tests were performed, and over 30,000 people had to be put on antibiotics.
After an accident on the Soviet’s part, it was discovered that they were testing some weapons that could be used in a bioterrorist attack. This knowledge, combined with the intel that defectors from the Soviet Union labs gave the U.S., convinced them that the Soviet Union wasn’t honoring the treaty it had previously signed.
One early example of a bioterrorist attack is when the Tartars catapulted dead plague-infested bodies into the city of Caffa.