Biowarfare in World War I
During World War I German forces in the United States secretly infected American livestock found for Europe with glanders and anthrax. Thousands of horses were killed, but American troops in Europe were largely unaffected. Chemical warfare was by far a larger concern than biological warfare during World War I: nitrogen mustard, phosgene and chlorine gas injured or killed hundreds of thousands of troops. In 1925, thirty-eight countries signed the Geneva Protocol prohibiting the use of biological and chemical weapons. Japan refused to sign the Geneva Protocol.
Interestingly, research and production of biological weapons was not prohibited by the Geneva Protocol.
Biowarfare in World War II
During World War II, Japan began experiments using biological agents on civilians and prisoners held in Manchuria. A bio-warfare unit, Unit 731, disguised as a water-purification plant was built outside of Harbin, Manchuria. A second unit, Unit 100, was built near Changchun. Anthrax, cholera, plague, typhoid and a number of other agents were used in field tests and resulted in the deaths of tens of thousands of people.
In one experiment, clay pots containing infected fleas and grain were dropped over areas in Manchuria and China. The grain attracted rats; the rats became infected from the fleas and dispersed to spread disease into the human population.
Plague bacteria, Yersinia pestis, was released by the Japanese at Chuhsien and later dropped from planes at Ninpo and Chinhua. Approximately 120 people were killed as a result of these attacks. However, in 1941 a serious plague epidemic began following release of Yersinia pestis in Suiyuan and Ninghsia provinces.
British Biowarfare Research
At the same time Allied forces were also experimenting with biological agents. The British experimented with anthrax on Gruinard Island off the coast of Scotland. A bomb was used to disseminate anthrax. Although the Island was thought to be far enough from shore for testing to be safe, an outbreak of anthrax occured in sheep and cattle on the coast of Scotland in 1943. The oubreak resulted in discontinuation of testing.
United States Biowarfare Research
The United States established a major biological weapon and defence research facility at Fort Detrick, Maryland and later developed smaller facilities in Dugway, Utah and Pine Bluff, Arkansas. A number of agents were investigated by the U.S., and in 1955, Pine Bluff began production of large quantities of Francisella tularensis, the causative agent of tularaemia.
Canada Biowarfare Research
Canada was also involved in research into the use of biological agents. Canada participated with the U.S. and Britain allowing field studies in remote areas of Canada.
Soviet Union Biowarfare Research
Meanwhile, the Soviet Union had been performing its own experiments with biological agents. Soviet research was directed toward plague, Marburg virus, smallpox and anthrax. The Soviets produced huge quantities of biological agents that could be loaded into missiles for deployment.