Entomological warfare (EW) is a type of biological warfare that uses insects to interrupt supply lines by damaging crops, or to directly harm enemy combatants and civilian populations. There have been several programs which have attempted to institute this methodology; however, there has been limited application of entomological warfare against military or civilian targets, Japan being the only state known to have verifiably implemented the method against another state, namely the Chinese during World War II. However, EW was used more widely in antiquity, in order to repel sieges or cause economic harm to states. Research into EW was conducted during both World War II and the Cold War by numerous states such as the Soviet Union, United States, Germany and Canada. There have also been suggestions that it could be implemented by non-state actors in a form of bioterrorism. Under the Biological and Toxic Weapons Convention of 1972, use of insects to administer agents or toxins for hostile purposes is deemed to be against international law.
Description EW is a specific type of biological warfare (BW) that uses insects in a direct attack or as vectors to deliver a biological agent, such as plague or cholera. Essentially, EW exists in three varieties. One type of EW involves infecting insects with a pathogen and then dispersing the insects over target areas."An Introduction to Biological Weapons, Their Prohibition, and the Relationship to Biosafety ", The Sunshine Project, April 2002, accessed December 25, 2008. The insects then act as a vector, infecting any person or animal they might bite. Another type of EW is a direct insect attack against crops; the insect may not be infected with any pathogen but instead represents a threat to agriculture. The final method of entomological warfare is to use uninfected insects, such as bees, to directly attack the enemy.Lockwood, Jeffrey A. Six-legged Soldiers: Using Insects as Weapons of War, Oxford University Press, USA, 2008, pp. 9–26, ().
Early history Entomological warfare is not a new concept; historians and writers have studied EW in connection to multiple historic events. A 14th-century plague epidemic in Asia Minor that eventually became known as the Black Death (carried by fleas) is one such event that has drawn attention from historians as a possible early incident of entomological warfare. That plague's spread over Europe may have been the result of a biological attack on the Crimean city of Kaffa by the Golden Horde.Kirby, Reid. "Using the flea as weapon", ( via findarticles.com), Army Chemical Review, July 2005, accessed December 23, 2008.
According to Jeffrey Lockwood, author of Six-Legged Soldiers (a book about EW), the earliest incident of entomological warfare was probably the use of bees by early humans.Baumann, Peter. "", Laramie Boomerang, October 18, 2008, accessed December 23, 2008. The bees or their nests were thrown into caves to force the enemy out and into the open. Lockwood theorizes that the Ark of the Covenant may have been deadly when opened because it contained deadly fleas."UW Professor Examines Biological Setting of Egyptian Plagues ", (Press release), University of Wyoming, December 12, 2005, accessed December 23, 2008.
During the American Civil War the Confederacy accused the Union of purposely introducing the harlequin bug in the South. These accusations were never proven, and modern research has shown that it is more likely that the insect arrived by other means. The world did not experience large-scale entomological warfare until World War II; Japanese attacks in China were the only verified instance of BW or EW during the war.Peterson, R.K.D. "The Role of Insects as a Biological Weapon" , Department of Entomology, Montana State University, notes based on seminar, 1990, accessed December 25, 2008. During, and following, the war other nations began their own EW programs.
World War II
France France is known to have pursued entomological warfare programs during World War II. Like Germany, the nation suggested that the Colorado potato beetle, aimed at the enemy's food sources, would be an asset during the war.Lockwood, Jeffrey A. "Bug Bomb", Boston Globe, October 21, 2007, accessed December 23, 2008. As early as 1939 biological warfare experts in France suggested that the beetle be used against German crops.
Germany Germany is known to have pursued entomological warfare programs during World War II. The nation pursued the mass-production, and dispersion, of the Colorado potato beetle (Lepinotarsa decemlineata), aimed at the enemy's food sources. The beetle was first found in Germany in 1914, as an invasive species from North America. There are no records that indicate the beetle was ever employed as a weapon by Germany, or any other nation during the war.Heather, Neil W. and Hallman, Guy J. Pest Management and Phytosanitary Trade Barriers ([Google Books]), CABI, 2008, pp. 17–18, (). Regardless, the Germans had developed plans to drop the beetles on English crops.
Germany carried out testing of its Colorado potato beetle weaponization program south of Frankfurt, where they released 54,000 of the beetles. In 1944, an infestation of Colorado potato beetles was reported in Germany. The source of the infestation is unknown, but speculation has offered three alternative theories as to the origin of the infestation. One option is Allied action, an entomological attack, another is that it was the result of the German testing, and another more likely explanation is that it was merely a natural occurrence.
Canada Among the Allied Powers, Canada led the pioneering effort in vector-borne warfare. After Japan became intent on developing the plague flea as a weapon, Canada and the United States followed suit. Cooperating closely with the United States, Dr. G.B. Reed, chief of Kingston's Queen's University's Defense Research Laboratory, focused his research efforts on mosquito vectors, biting flies, and plague-infected fleas during World War II. Much of this research was shared with or conducted in concert with the United States.
Canada's entire bio-weapons program was ahead of the British and the Americans during the war. The Canadians tended to work in areas their allies ignored; entomological warfare was one of these areas. As the U.S. and British programs evolved, the Canadians worked closely with both nations. The Canadian BW work would continue well after the war,Wheelis, Mark, et al. Deadly Cultures: Biological Weapons Since 1945, (Google Books), Harvard University Press, 2006, pp. 84-90, (). including entomological research.
Japan
Japan used entomological warfare on a large scale during World War II in China. Unit 731, Japan's biological warfare unit, led by Lt. General Shirō Ishii, used plague-infected fleas and flies covered with cholera to infect the population in China. Japanese Yagi bombs developed at Pingfan consisted of two compartments, one with houseflies and another with a bacterial slurry that coated the houseflies prior to release. The Japanese military dispersed them from low-flying airplanes; spraying the fleas from them and dropping the Yagi bombs filled with a mixture of insects and disease. Localized and deadly epidemics resulted and nearly 500,000 Chinese died of disease.Lockwood, Jeffrey A. "Six-legged soldiers ", The Scientist, October 24, 2008, accessed December 23, 2008.Novick, Lloyd and Marr, John S. Public Health Issues Disaster Preparedness, (Google Books), Jones & Bartlett Publishers, 2001, p. 87, (). An international symposium of historians declared in 2002 that Japanese entomological warfare in China was responsible for the deaths of 440,000. It should also be noted that the U.S. granted Japanese 731 officials immunity from prosecution in exchange for their research, and members of the former 731 Unit went on to have successful careers in business, academia, and medicine.
United Kingdom A British scientist, J.B.S. Haldane, suggested that Britain and Germany were both vulnerable to entomological attack via the Colorado potato beetle. In 1942 the United States shipped 15,000 Colorado potato beetles to Britain for study as a weapon.
Cold War
Soviet Union
The Soviet Union researched, developed and tested an entomological warfare program as a major part of an anti-crop and anti-animal BW program. The Soviets developed techniques for using insects to transmit animal pathogens, such as: foot and mouth disease—which they used ticks to transmit; avian ticks to transmit Chlamydophila psittaci to chickens; and claimed to have developed an automated mass insect breeding facility, capable of outputting millions of parasitic insects per day.Ban, Jonathan. "Agricultural Biological Warfare: An Overview ", The Arena, June 2000, Paper #9, Chemical and Biological Arms Control Institute, via Memorial Institute for the Prevention of Terrorism, accessed December 25, 2008.
United States
The United States seriously researched the potential of entomological warfare during the Cold War. Labs at Fort Detrick were set up to produce 100 million yellow fever-infected mosquitoes per month deliverable by bombs or missiles. The facility could also breed 50 million fleas per week and later experimented with other diseases such as anthrax, cholera, dengue, dysentery, malaria, relapsing fever, and tularemia. A U.S. Army report titled "Entomological Warfare Target Analysis" listed vulnerable sites within the Soviet Union that the U.S. could attack using entomological vectors. The military also tested the mosquito biting capacity by dropping uninfected mosquitoes over U.S. cities.
North Korean and Chinese officials leveled accusations that during the Korean War the United States engaged in biological warfare, including EW, in North Korea. The claim is dated to the period of the war, and has been thoroughly denied by the U.S.Regis, Ed. "Wartime Lies?", The New York Times, June 27, 1999, accessed December 24, 2008. In 1998, Stephen Endicott and Edward Hagerman claimed that the accusations were true in their book, The United States and Biological Warfare: Secrets from the Early Cold War and Korea.Endicott, Stephen, and Hagerman, Edward. The United States and Biological Warfare: Secrets from the Early Cold War and Korea, (Google Books, relevant excerpt), Indiana University Press, 1998, pp. 75-77, (), links accessed December 24, 2008. The book received mixed reviews, some called it "bad history" and "appalling", while others praised the case the authors made."Reviews of The United States and Biological Warfare: secrets of the Early Cold War and Korea", York University, compiled book review excerpts, accessed December 24, 2008. Other historians have revived the claim in recent decades as well. The same year Endicott and Hagerman's book was published Kathryn Weathersby and Milton Leitenberg of the Cold War International History Project at the Woodrow Wilson Center in Washington released a cache of Soviet and Chinese documents which revealed the North Korean claim was an elaborate disinformation campaign.Auster, Bruce B. "Unmasking an Old Lie ", U.S. News & World Report, November 16, 1998, accessed December 24, 2008.