Entomological warfare Entomological warfare ( EW ) is a type of biological warfare that uses insects to attack the enemy . The concept has existed for centuries and research and development have continued into the modern era . EW has been used in battle by Japan and several other nations have developed and been accused of using an entomological warfare program . Description . Entomological warfare ( 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 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 . 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 . 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 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 . According to Jeffrey Lockwood , author of " " ( a book about EW ) , the earliest incident of entomological warfare was probably the use of bee s by early humans . 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 . 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 it 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 . During , and following , the war other nations began their own EW programs . World War II . 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 , including entomological research . 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 . 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 . 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 , 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 still another more likely explanation is that it was merely a natural occurrence . Japan . Japan used entomological warfare on a large scale during World War II in China . Unit 731 , Japan ' s infamous biological warfare unit led by Lt . General Shirō Ishii , used plague - infected flea s and flies covered with cholera to infect the population in China . The Japanese military dispersed the insects by spraying them from low - flying airplanes and dropping bombs filled with a mixture of insects and disease . Localized and deadly epidemics resulted and nearly 500 , 000 Chinese died of disease . An " international symposium " of historians declared in 2002 that Japanese entomological warfare in China was responsible for the deaths of 440 , 000 . The late Ban Shigeo , a technician at the Japanese Army ' s 9th Technical Research Institute , left a rare and valuable account of the activities of Noborito Research Institute which was published in Rikugun Noborito Kenkyujo no shinjitsu - The Truth About the Army Nororito Institute available only in the Japanese language . Of the Japanese Army ' s ten numbered institutes , only the 9th Army Technical Research Institute came under the covert operations section of the Army General Staff ' s Second Bureau ( Intelligence ) . On the sensitive issue of Japanese biological warfare , Ban did not shrink from including an account of his trip to Nanking in 1941 to participate in the testing of poisons on Chinese prisoners . One of his book ' s contributions is to further tie Noborito to the Japanese Army ' s infamous Unit 731 , which participated in biomedical research . When the war ended , the US Army quietly enlisted certain members of Noborito in its efforts against the communist camp in the early years of the Cold War . The author notes near the end of the book that Ban led the " chemical section " of a US clandestine unit hidden within Yokosuka naval base during the Korean War , and then worked on unspecified projects inside the United States from 1955 to 1959 , before returning to Japan to enter the private sector . Shirō Ishii of Unit 731 , having not been charged as a war criminal , also continued his work to consult with American authorities , especially during the height of the Cold War , and died in 1959 of throat cancer . In 1989 , a British study of Unit 731 strongly supported the theory of United States - Japanese BW culpability in Korea . Chinese experts doggedly insist today that BW weapons created in an American - Japanese collaboration were used in the Korean war . Further evidence that Japanese continued to assist the United States Chemical , Biological warfare , as well as Radiological effects and Entomological warfare program efforts continued after the Korean war into Vietnam includes a visit to Rocky Mountain Arsenal in September 1962 by Japanese delegation I - 63 . Among many other activities , from January 1962 - October 1969 , Rocky Mountain Arsenal “ grew , purified and biodemilitarized ” plant pathogen wheat stem rust [ Puccinia graminis , var . tritici ] ( Agent TX ) for the Air Force biological anti - crop program . TX - treated grain was grown at the Arsenal from 1962 - 1968 in Sections 23 - 26 . Unprocessed TX was also transported from Beale AFB for purification , storage , and disposal . Trichothecenes Mycotoxin is a toxin that can be extracted from Wheat Stem Rust and Rice Blast and can kill or incapacitate depending on the concentration used . The “ red mold disease ” of wheat and barley in Japan is prevalent in the region that faces the Pacific Ocean . Toxic trichothecenes , including nivalenol , deoxynivalenol , and monoace tylnivalenol ( fusarenon - X ) from Fusarium nivale , can be isolated from moldy grains . In the suburbs of Tokyo , an illness similar to “ red mold disease ” was described in an outbreak of a food borne disease , as a result of the consumption of Fusarium - infected rice . Ingestion of moldy grains that are contaminated with trichothecenes has been associated with mycotoxicosis . 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 tick s to transmit . The nation also used avian tick s to transmit " Chlamydophila psittaci " to chickens . In addition , the Soviet Union claimed to have developed an automated mass insect breeding facility , capable of outputting millions of parasitic insects per day . United States . The United States seriously researched the potential of entomological warfare during the Cold War . The United States military developed plans for an entomological warfare facility , designed to produce 100 million yellow fever - infected mosquitoes per month . 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 . In 1998 , Stephen Endicott and Edward Hagermann claimed that the accusations were true in their book , " The United States and Biological Warfare : Secrets from the Early Cold War and Korea " The book received mixed reviews , some called it " bad history " and " appalling " , while other praised the case the authors made . Other historians have revived the claim in recent decades as well . The same year Endicotts ' 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 . During the 1950s the United States conducted a series of field tests using entomological weapons . Operation Big Itch , in 1954 , was designed to test munitions loaded with uninfected fleas ( " Xenopsylla cheopis " ) . Big Itch went awry when some of the fleas escaped into the plane and bit all three members of the air crew . In May 1955 over 300 , 000 yellow fever mosquitoes ( " Aedes aegypti " ) were dropped over parts of the U . S . state of Georgia to determine if the air - dropped mosquitoes could survive to take meals from humans . The mosquito tests were known as Operation Big Buzz . Operation Magic Sword was a 1965 U . S . military operation designed to test the effectiveness of the sea - borne release of insect vectors for biological agents . The U . S . engaged in at least two other EW testing programs , Operation Drop Kick and Operation May Day . A 1981 Army report outlined these tests as well as multiple cost - associated issues that occurred with EW . The report is partially declassified — some information is blacked out , including everything concerning " Drop Kick " — and included " cost per death " calculations . The cost per death , according to the report , for a vector - borne biological agent achieving a 50 % mortality rate in an attack on a city was $ 0 . 29 in 1976 dollars . Such an attack was estimated to result in 625 , 000 deaths . The United States has also applied entomological warfare research and tactics in non - combat situations . In 1990 the U . S . funded a $ 6 . 5 million program designed to research , breed and drop caterpillar s . The caterpillars were to be dropped in Peru on coca fields as part of the American War on Drugs . As recently as 2002 U . S . entomological anti - drug efforts at Fort Detrick were focused on finding an insect vector for a virus that affects the opium poppy . Bioterrorism . Clemson University ' s Regulatory and Public Service Program listed " diseases vectored by insects " among bioterrorism scenarios considered " most likely " . Because invasive species are already a problem worldwide one University of Nebraska entomologist considered it likely that the source of any sudden appearance of a new agricultural pest would be difficult , if not impossible , to determine . Lockwood considers insects a more effective means of transmitting biological agent s for acts of bioterrorism than the actual agents . Insect vector s are easily gathered and their eggs easily transportable without detection . Isolating and delivering biological agents , on the other hand , is extremely challenging and hazardous . In one of the few suspected acts of entomological bioterrorism an eco - terror group known as The Breeders claimed to have released Mediterranean fruit flies ( medflies ) amidst an ongoing California infestation . Lockwood asserts that there is some evidence the group played a role in the event . The pest attacks a variety of crops and the state of California responded with a large - scale pesticide spraying program . At least one source asserted that there is no doubt that an outside hand played a role in the dense 1989 infestation . The group stated in a letter to then Los Angeles Mayor Tom Bradley that their goals were twofold . They sought to cause the medfly infestation to grow out of control which , in turn , would render the ongoing Malathion spraying program financially infeasible . Legal status . The Biological and Toxic Weapons Convention ( BWC ) of 1972 does not specifically mention insect vectors in its text . The language of the treaty , however , does cover vectors . Article I bans " Weapons , equipment or means of delivery designed to use such agents or toxins for hostile purposes or in armed conflict . " It would appear , due to the text of the BWC , that insect vectors as an aspect of entomological warfare are covered and outlawed by the Convention . The issue is less clear when warfare with uninfected insects against crops is considered .