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Biological warfare -

We tend to associate the term “biological warfare” with bacteria, viruses, toxins, and other living agents that can affect humans. The use of insects is a type of biological warfare.

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Entomological warfare -

This specific type of biological warfare is called entomological warfare (EW). Insects can harm the enemy in a number of ways. They can be used as crop pests, to spread diseases, and as literal weapons. 

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Scorpion pots -

Insects have been used as weapons for thousands of years. One of the earliest examples dates back to 198 ACE, during the Second Roman–Parthian War. To defend the city of Hatra from the Romans, King Barsamia threw scorpion-stuffed pots at the enemy.

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Beetles -

It’s believed that the bug bombs used by the Parthians also contained rove beetles. These beetles from the genus Paederus contain a compound called pederin, which causes dermatitis and blistering when it comes into contact with the skin.

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Bees -

During the Third Mithridatic War, King Mithridates VI of Pontus ordered for “grayanotoxin-laden honey created by rhododendron-foraging honey bees” to be left along roads for the Romans. Basically, the honey was tainted with a toxin.

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Honey -

Roman soldiers who consumed this honey got sick and suffered hallucinations. They dubbed it “mad honey.”

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Stinging attack -

The Mithridates were pioneers of entomological warfare. They also dug sapper tunnels beneath battlefields and bees and hornets were then released to attack the Romans.

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Plague fleas -

The Bubonic Plague decimated millions during the 14th and 15th centuries. It’s believed that the Mongol Tartars are to blame for its spread to Europe. When sieging the city of Kaffa (now Fedosia), they catapulted plague-infested cadavers over the walls.

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Plague fleas -

The disease spread through fleas and the city fell in 1346. Some people managed to escape and are believed to have introduced the plague into Europe.

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American Civil War -

The Confederacy accused the Union of introducing the harlequin bug (Murgentia histrionica) into the South with the intention of damaging their crops. The allegation, however, was never proven.

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World War II: Japan -

Unit 731 was a covert Japanese biological weapons research and development facility. There, researchers actually built a bomb filled with plague-infected fleas and dropped it in Changde and Ningbo in China to test it.

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World War II: Japan -

This was a test for Operation Cherry Blossoms at Night (aka Operation PX). The goal was to drop the plague-infected fleas onto parts of California. Luckily, Japan surrendered two weeks before the planned attack.

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World War II: Germany -

Hitler was convinced that the Americans were going to use the Colorado potato beetle to destroy German crops, so they started breeding them to be able to study them. The Nazi experiment quickly turned into an offensive plan, which they tested in fields in Speyer, Germany.

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World War II: Allies -

It turns out that Hitler’s concerns were founded. In 1942, the US actually sent 15,000 beetles to the UK to be studied as a biological weapon. Reportedly, the French had been researching the beetles since 1939 and conducting release trials.

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Post-war beetles -

In 1950, the East German government accused the Americans of dropping potato beetles over their fields to sabotage their crops. "There is no factual basis for the story about the Yankee beetles at all," said Erhard Geissler, an expert in biological warfare at the Max Delbruck Centre for Molecular Medicine.

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Korean War -

During the Korean War, the Chinese claimed that the Americans were spreading "disease-carrying anthomyiid flies, springtails, and stoneflies with P-51 fighters." The US has always denied the allegations.

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Operation Big Itch -

In 1954, the U.S. military actually ran tests on whether or not fleas could be put in bombs and dropped from the air. Operation Big Itch was conducted at Dugway Proving Ground in Utah.

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Operation Big Itch -

For the test, they first used uninfected tropical rat fleas. The fact that the fleas were not carrying any disease was good news for the pilot, copilot, and personnel aboard the plane, as some fleas escaped and bit them.

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Operation Big Itch -

The operation was successful in the end, and the recommendation was that "continued research of Biological Warfare with arthropod vectors apparently is justified," according to the official unclassified files. But because fleas proved too difficult to control, the US refocused their research on mosquitoes.

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Operation Big Buzz -

Operation Big Buzz took place in 1955. The aim was to simulate a mosquito-based attack. To do so, hundreds of thousands of Aedes aegypti mosquitoes (aka yellow fever mosquitoes) were dropped onto an area of Georgia. The mosquitoes were, however, uninfected.

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Operation Big Buzz -

Both guinea pigs and human volunteers were used as test subjects. The test was a success, but its use in real warfare would be rather expensive, according to a 1981 U.S. Army report.

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Operation Big Buzz -

The report found that around 225,000 infected mosquitoes would be needed in order to attack a battalion. This would have a cost of approximately US$27,000 (around US$131,900 in today’s money).

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Bioterrorism -

In 1989, a medfly outbreak in California concerned the authorities. The Mediterranean fruit flies caused millions in damage, and a number of eradication programs were implemented. But this was no ordinary infestation.

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Bioterrorism -

In December 1989, a number of California politicians and media outlets received a letter from a group called 'The Breeders,' claiming to be responsible for the medfly outbreak. The attack was retaliation for the damage caused by the state’s air spraying of the insecticide Malathion.

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Bioterrorism -

The letter read: "Every time the copters go up to spray, we'll go into virgin territory or old Medfly problem areas and release a minimum of several thousand blue-eyed Medflies. We are organized, patient, and determined."

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Bioterrorism -

In March 1990, the state stopped its Malathion aerial spraying program and introduced sterilized medflies instead, to control the population.

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War on Drugs -

In 1990, the Bush administration thought they’d enlist Eloria noyesi, the coca tussock moth, in the War on Drugs. The idea was to drop millions of coca-eating caterpillars onto coca fields in Bolivia and Peru.

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War on Drugs -

Bolivia rejected the idea because of the damage it would cause to the local ecosystem. Colombia later looked into the idea, but ended up abandoning it for the same reasons. There is no evidence that the US ever went ahead with the plan.

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Insect Allies -

Insect Allies is a program run by the U.S. Defense Advanced Research Project Agency (DARPA). They research the use of insects as vectors for gene editing. This means that insects could potentially be used to deliver viruses that can genetically edit crops.

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Insect Allies -

While the program seems promising, there are concerns that it can be misused for developing biological weapons.

Sources: (Montana State University) (History) (Entomology Today) (The Smoking Gun) (The Guardian) (BBC) (Grunge) 

See also: The brutal history of starvation in warfare 

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