16 of the Most Horrifying Bug Infestations in History

16 of the Most Horrifying Bug Infestations in History

Trista - April 5, 2019

The book of Exodus, in the Bible, speaks of plagues of frogs, gnats, and locusts (among other epidemics) that God brought against the land of Egypt to force Pharaoh to free the Hebrew slaves. People who have suffered from bug infestations in recent years might understand why a bunch of locusts and gnats would be enough to make Pharaoh relent, at least temporarily. In small numbers, they can be a nuisance. In large numbers, though, they can bring society to a standstill. A bug infestation can cause widespread ecological damage, disrupt economic life, and even cause death.

The twentieth and twenty-first centuries saw plagues of snakes, locusts, crickets, grasshoppers, cicadas, moths, caterpillars, giant hornets, and more. Some of them devoured crops or destroyed trees, causing harm to local economies and wildlife. Others caused human and animal deaths as a result of poisonous bites or stings. Some of the swarms were so intense that they could actually be seen by weather satellites floating above the earth’s atmosphere.

Imagine yourself being suddenly surrounded by apocalyptic hordes of snakes or ferocious spiders. Imagine that you are at home and find that an aptly named species, “crazy ants,” have suddenly invaded your home with such intensity that your floor looks like it is moving. Likewise, imagine that you are a farmer and wake up to find that hordes of crickets, grasshoppers, or locusts have eaten all of your crops.

Unfortunately, these infestations seem to be happening with more and more frequency, probably as a result of human-made activity. Conditions due to climate change create perfect environments for mosquitoes, grasshoppers, and crickets to appear in ever-increasing numbers. Calling exterminators and using pesticides will not be enough to halt these infestations in the future. They will probably continue to get worse until the conditions associated with climate change are reversed. Until then, we will have to learn to live with the reality of massive bug infestations.


16 of the Most Horrifying Bug Infestations in History
A massive hedge of Ermine Moth caterpillar webs. Daily Mail UK

16. Caterpillars Spin Web of Doom in 2009

Ermine moths are common to tropical areas and part of Europe and are considered to be nothing more than minor pests. They aren’t dangerous, at least not on their own. The caterpillars of ermine moths are known to get together and spin communal webs, particularly after having a meal. Many people see the webs and mistake them for spider webs, so they quickly back away. After all, who wants to get trapped in a spider web in a manner akin to what Frodo had to endure in Lord of the Rings or what Harry and Ron had to escape in Harry Potter and the Chamber of Secrets?

Throughout Europe, the moths occasionally gather in large enough clusters to make particularly spectacular webs. Some of their webbed “victims” have included entire trees and hedges and even a parked car! While the ermine moth itself is a beautiful, delicate looking moth, there is no joke about stumbling upon webs that looks like they could have come straight out of Shelob’s Lair.

16 of the Most Horrifying Bug Infestations in History
Dani Siddle holding a female cicada in New York. Cicada Mania.

15. Periodical Cicada Invasions

Cicadas are periodical insects that gestate underground and only emerge in periods of every 13 to 17 years. They tend to live most of their lives underground, from the time that they hatch, and appear only to mate. The eggs are then buried underground, and the life cycle begins once again. This is why they arise only once every 13 to 17 years, depending on the species. When they do emerge, they can create massive infestations that can disrupt local economies, depending on how severe the swarms become. That said, there are plenty of cicada fans who wait patiently for the next encounter.

In the United States, cicadas are most common on the East Coast and the Midwest. When they emerge, billions of the bugs swarm towns and cities. When they die, especially en masse, they emit a foul odor that can become nauseating. That is what happened in the summer of 2013, when a cicada cycle brought billions of the bugs to the East Coast, infesting areas from Washington, DC to New York City. Cicada fans took the rare opportunity to observe them first hand, while most people found them to be a nuisance at best. Due to climate change, their cycles may begin to change unpredictably.

There are also annual cicadas that appear each summer in warmer parts of the central and Eastern United States. Whether you think their song is a beauty of summer or a nuisance, cicadas are here to stay at least every year, and some years… watch out for the swarm!

16 of the Most Horrifying Bug Infestations in History
A common grasshopper. Song of Insects.

14. Grasshopper Swarms

The arid land of New Mexico and Arizona makes a perfect breeding ground for grasshoppers. Freezing temperatures and wet weather during the winter usually kill many of the eggs that are incubating, but but unusually mild winters, which will likely increase due to climate change, create the perfect breeding ground for grasshopper invasions. Drought conditions ensured that many of the eggs would survive, resulting in an overly large grasshopper population. They began hatching in the spring, and by Memorial Day at the end of May, people started noticing that grasshoppers were everywhere. The onslaught became so severe that thick clouds of grasshoppers showed up on weather radar as if they were rain clouds.

Grasshoppers latched onto people’s faces as they were walking down sidewalks, splattered on car windshields, and terrorized gardens and farms. City departments encouraged people not to use pesticides, however, because the grasshoppers could fly as far as three to five miles. Pesticides would only kill a few of the grasshoppers while harming the local ecosystem of insects. The only solution was to wait out the infestation until it finally came to an end. Milder winters and longer, more intense droughts – as a result of global warming – mean that these rare infestations may become much more common.

16 of the Most Horrifying Bug Infestations in History
A plague carrying flea. NPR.

13. Plague Fleas

Few insect infestations have done as much damage as the plague fleas that started the waves of the Black Death throughout Europe. While people living at the time had no way of knowing it was the tiny fleas on rats, not the rats themselves, that were causing the plague, we now know the full devastation that unnaturally high populations of plague-infected fleas had throughout Europe.

Research of the periods of the Black Death indicate that plague years tended to occur after a warm, wet summer in the areas in which the fleas were endemic throughout the Middle East and northern Africa. The fleas then reached Europe through merchant vessels and began to infect a population with no natural resistance to the disease.

Plague fleas can actually still be encountered in the American Southwest, and the likelihood of running into one may be increasing with climate change. Campers in some Southwestern national parks are given warnings on how to avoid attracting fleas to their camps to reduce the risk of exposure. Thankfully, the plague is now a treatable disease, but that’s of little comfort to the hundreds of thousands who died thanks to medieval Europe’s flea infestation.

16 of the Most Horrifying Bug Infestations in History
A maize weevil. Wikipedia.

12. Colonial Weevils

When British Colonists arrived in what would become the United States, they found countless things they didn’t expect. From hostile natives to bizarre wildlife such as the turkey, the New World was truly just that. One very small surprise led to long-term food stability issue for the early settlers: weevils.

The Maize Weevil is a small brown beetle that can easily inflict ruinous damage on multiple crops including wheat, corn, rice, and more. Warm, dry winters led to huge outbreaks of weevils that did their best to decimate the staple crops of the early colonizers.

Because they weren’t content with just destroying crops, weevils also liked to tunnel into loaves of bread and hardtack, sometimes becoming trapped or dying in them leaving an unfortunate, crunchy surprise for early colonists. While weevils still exist and are active throughout the United States, modern farming methods have rendered them largely incapable of doing too much harm to the crops we rely on.

16 of the Most Horrifying Bug Infestations in History
An early illustration of a mosquito. Lewis-Clark.org.

11. 1793 Yellow Fever Epidemic

While many think of Yellow Fever as a largely Caribbean disease, Philadelphia, Pennsylvania played host to a massive epidemic of the disease in 1793. August and September were widely considered “sickly season” throughout the coastal United States at the time, due to the common fevers that popped up throughout the season. However, no one was prepared for the Yellow Fever epidemic that hit during that season in 1793.

Due to many factors, including a slave rebellion in Saint-Domingue that led to numerous refugees, many of whom may have been carrying the infection and an unusually hot and wet summer, conditions were ripe for the outbreak of a mosquito-borne illness.

The first two to die were both new immigrants, one from Ireland and the other from Saint-Domingue, likely fleeing the slave uprising. It is quite possible that the refugee from Saint-Domingue was patient zero, as Yellow Fever was endemic in the area. Regardless of who was the first, the heavy mosquito population of that summer ultimately led to the deaths of over 5,000 people in only two short months.

16 of the Most Horrifying Bug Infestations in History
An illustration of cockroaches. University of South Florida.

10. Cockroaches Freaked Out Settlers

La Cucaracha may be a cute little ditty now, but to early colonial settlers the cockroach was no joke. Described as “a new annoyance” by Captain John Smith in his 1624 Generall Historie of Virginia, New England, and the Summer Isles, early settlers were horrified by the huge, prehistoric looking insects.

The Spanish word cucaracha, which translates to contemptible little caterpillar was widely mangled by the English speaking settlers, and morphed over time into the now recognizable English word cockroach. Interesting, the Spanish viewed the cockroach as a kind of caterpillar while the English colonists viewed it as a form of moth. Neither are correct, with the cockroach actually being of the order Blattodea, which includes the similarly onerous pests termites.

Doubtless new settlers struggled to keep their homes, barns, and granaries free of the pests and likely saw some food spoilage due to the incursions of roaches. Thomas Moffatt, an English physician, hated roaches far more than Smith and wrote of them as, “nasty, cruel, rough, theeving, living of nocturnal depredations after an infamous manner.” Harsh. One can only imagine his reaction if he’d known what we know now, that those cruel, rough little things will outlive us, even in the case of a nuclear apocalypse.

16 of the Most Horrifying Bug Infestations in History
Raspberry crazy ants spread throughout Texas. AP/Fox News.

9. Crazy Ants Ravaged Texas

“Crazy ants” are cousins to fire ants but considerably more dangerous. They originated in South America and arrived in Texas during the 1930s on board a cargo ship. Since then, they spread to 27 counties throughout the state, wreaking a trail of havoc and destruction. They are particularly pernicious around electrical systems, where they chew through wiring and insulation. They have been known to destroy computers and even short out electrical equipment in plants, causing them to shut down temporarily. More horrifying is the fact that they reproduce at such a rapid rate that a one-acre field can quickly become swarmed by as many as 20 billion crazy ants.

Climate change has witnessed the expansion of many kinds of ants, including the fire and “crazy” ants, outside of their normal endemic territories. With the unpredictable nature of expansion of species, it is quite possible ants like the crazy ant will expand into areas where they lack natural predators or have an overabundance of food, the types of checks and balances that nature relied on to manage populations before the intervention of human-generated climate change.

16 of the Most Horrifying Bug Infestations in History
An Emerald Ash Borer. Wikipedia.

8. Emerald Ash Borers Destroying America’s Forests

Who could have known that beautiful jade-green iridescent beetles would be responsible for causing millions of dollars in damage to US forestry operations while destroying landscaping trees in millions of Americans’ yards. Sadly, this is now the case ever since the introduction of the Emerald Ash Borer to the United States from Asia in the 20th century.

Every North American ash species is susceptible to the damage from the ash borer, which bores into ash trees and kills them, as their name implies. When the Emerald Ash Borer reaches a new region of the United States, all ash trees within that region are expected to survive for no longer than 10 years. Eventually, the entire United States will lose their ash tree population if no permanent solution is found to the invasive beetle.

While it is not certain, it is widely believed that the Emerald Ash Borer was first introduced to the United States in shipping crates coming from overseas. It highlights one of the dangers of international commerce, particularly in an era seeing increasing climatological and biological changes due to climate change.

16 of the Most Horrifying Bug Infestations in History
An illustration of Phylloxera. Wikipedia.

7. A Tiny Bug Devastated France’s Wine Industry

Lest you think the United States is the only victim of invasive insect species, let’s turn our attention to Phylloxera, a tiny aphid-like insect that was accidentally introduced to France from the United States. Our bad, guys.

Phylloxera have a complicated life cycle, many stages of which can greatly harm the vines they use for reproduction, food, and shelter. They lay eggs in the roots and stalks of vining plants, suck the sap out of the plants, and can also cause fungal infections in the rootstock. This combination of various assaults absolutely ravaged European grape production, as none of the European varieties had any natural resistance to the invasive New World insect.

It is estimated that as many as two-thirds of all grape vines in Western Europe were destroyed in the decade following the accidental introduction of the pest. European wine making saw a similarly drastic dip. A great deal of research went into grafting and cultivating grape stock that was hardier and resistant to the insect, as it could not be eradicated.

16 of the Most Horrifying Bug Infestations in History
A body louse. Wikipedia.

6. The Lice That Stopped Napoleon

We all likely know by now that attempting to conquer Russia in winter is a profoundly bad idea that just does not pan out for the invading armies. However, in the case of Napoleon Bonaparte, it was not only the cold that stopped his troops in their tracks.

Napoleon’s troops wanted to travel light, so they did not bring along changes of uniform or even underclothes. They wore the same uniform day after day, often without bathing. While gross and undoubtedly bad for morale, this also had the disastrous effect of allowing body lice to run rampant throughout his troops.

Body lice carry numerous diseases, including trench fever, relapsing fever, and epidemic typhus, and Napoleon soon found himself with forces that were greatly weakened, not only by the cold climate of Russia in winter, but by the body lice wounds and subsequent diseases brought about by their own short-sighted packing and lack of bathing. Combined with malnutrition from light rations and the bitter cold, it’s no doubt that his troops were in no condition to conquer a vast landmass. Still, being vanquished by a body louse is an awful way to lose a war…

16 of the Most Horrifying Bug Infestations in History
A scorpion. Odyssey.

5. Bug Warfare

As comical as it might sound to modern readers, insects actually have been used as weapons dating as far back as Ancient Greece. There are countless stories of hives of wasps and bees shaken and thrown over an enemies walls to help break sieges. While this may seem like something out of a skit, imagine how you’d feel trying to withstand a siege while being stuck by dozens of bees!

There are also stories of giving baskets full of venomous scorpions to enemies, which is as terrifying as it is poetic and creative. This method of insult (or murder) seems as though it would be at home on the pages of one of the great Greek tragedies.

In a more serious and malign iteration, Japanese force in World War II invested a great deal of time, money and energy into attempts to weaponize plague fleas in order to cause plague epidemics among allied soldiers. They loaded plague fleas into clay bombs, which they tested on some remote areas in China. Those areas did sustain small plague outbreaks, but the Japanese forces never achieved the level of contagiousness or lethality that they required for an effective weapon.

16 of the Most Horrifying Bug Infestations in History
A Mormon cricket. Flickr.

4. Mormon Crickets Increase Their Infestations

Mormon crickets are named after the Mormon settlers that settled expanses of America’s West. The bugs average in at three inches in length and descend upon areas of Idaho, Nevada, Montana, Colorado, Oregon, Washington, Arizona, and Wyoming, usually every other year. Out-of-control swarms can devour crops, leading to substantial economic damage in the farm communities of the West. The gross factor increases exponentially when their dead carcasses pile up in roads, creating slicks that lead to car crashes. When crushed, the bugs are extraordinarily juicy, so roads and sidewalks coated with their carcasses can become as slick as ice.

While the crickets have troubled settlers for centuries, beginning in 2000, the biannual infestations became more regular, hitting the states every year with increasing intensity. In some places, Mormon cricket swarms were so dense that there were as many as 70 per square yard. Populations that high can destroy anything in their paths, decimating large farms within minutes. Being affected by crowds of Mormon crickets is just a fact of life for many in the affected areas, something that they have to get used to since they live in the region. However, it isn’t all bad news for those who can get past the gross factor: the giant bugs are known by the locals to be great for catching catfish.

16 of the Most Horrifying Bug Infestations in History
An Africanized bee. Flickr.

3. In 1985, Africanized Bees Arrived in Texas

Africanized bees, also known as killer bees, are a hybrid species that was created in Brazil in the 1950s to increase honey production. As happens all too often when plants and animals are used as science experiments, a group of the bees escaped their quarantine and began to build colonies throughout South America and into North America. Few people are actually stung to death by killer bees – usually only about one person per year in the United States – and even that number is almost always because the victim antagonized them. However, they are dangerous, as people found in 1985 when the bees were located in Texas.

Killer bees are known to attack anything that they believe is threatening the hive. They can chase people and animals for as much as a quarter of a mile, and when they travel as a swarm, they can overwhelm the victim by delivering thousands of bites. As many as 1000 people worldwide have died as a result of being attacked by hordes of killer bees. Since they first arrived in the United States in 1985, they have spread northward. Today, killer bees can be found all across the continental United States. Efforts to control and thwart their spread have been met with varying degrees of success.

16 of the Most Horrifying Bug Infestations in History
A mosquito. Texas Monthly.

2. 1980 Vampire Swarm of Mosquitoes Devastate Texas Farms

Texas is one of those states that is both blessed and cursed by its geography. Its massive land size and natural resources make it a producer of many products and goods that are used by people in America. Its long coastline that borders the Gulf of Mexico makes it prime real estate for hurricanes. When these massive storms find their way from the Atlantic Ocean to the Gulf of Mexico, the warm gulf waters cause them to intensify dramatically. When they make landfall, they can be catastrophic, bringing not only heavy wind and storm surges but also flooding.

When flat places like Texas flood, the water isn’t usually able to drain quickly; in the meantime, mosquitoes have a perfect environment for laying eggs, which can cause swarms of Biblical proportions. This is precisely what happened in August of 1980, following widespread flooding brought by Hurricane Allen. Billions of mosquito eggs hatched and swarmed local farms with such force that they drained the blood from cattle and horses. An estimated four million bites were required to kill each animal, an average of 5,300 bites per minute for 12 hours straight. The infestation lasted for weeks before it finally subsided.

16 of the Most Horrifying Bug Infestations in History
A volcanic snake. Flickr.

1. 1902 Volcanic Eruption Brings Apocalypse of Snakes

People who live on or near dormant volcanoes don’t tend to take the sleeping giant on their doorstep seriously. When the cataclysmic eruption comes, people tend to be entirely caught off guard, despite warnings in the forms of tremors, smoke plumes, and mini explosions. These eruptions tend to be so dangerous because historically, people tend to remain in their homes rather than flee to safety. That’s what happened when Mount Pelee, on the French island of Martinique, blew its gasket in 1902. The eruption was violent and caused massive damage. Out of a population of approximately 28,000 people, only two are known to have survived.

Before its eruption, Mount Pelee gave plenty of warning. Tremors and ash clouds in the days and weeks before the explosion caused a plague of pests to swarm villages and towns. The repertoire of pests included foot-long millipedes and colonies of red ants that bit people and animals incessantly. Moreover, with the pests came snakes. Hordes of poisonous snakes descended on Martinique in April 1902. At least 50 people and 200 animals died because of venomous bites. Those that survived the plague of snakes fell prey to the ensuing eruption, except for the two people that are known to have survived.


Where did we get this stuff? Here are our sources:

“Mt. Pelee Eruption (1902).” How Volcanoes Work.

“Georgis Parasitology for Veterinarians,” by Dwight D. Bowman. Elsevier Sanders. 2014.

“Africanized Bees.” Wikipedia.

“Invasion of Mormon crickets: Idaho hit with record-breaking swarms of insects,” by Associated Press. Daily Mail. July 13, 2017.

“Attack of the slimy caterpillar web.” Metrowebukmetro. May 26, 2009.

“Huge Numbers of Crickets are Invading Oklahoma,” by Pamela Engel. Business Insider. September 5, 2013.

“Cicada.” Wikipedia.

“Grasshopper Swarms So Dense They Show Up On Radar,” by Dina Abou Salem.” ABC News. June 2, 2014.

“Houston braces for invasion of ‘Crazy Ants.'” Fox News. October 21, 2015.

“We’ve Identified Those Bugs Infesting Burning Man, And It’s Not Pretty,” by Annalee Newitz. Gizmodo. August 20, 2015.

“Aggressive Mosquitoes Bugging LGA Airport Workers Since Construction Began,” by Katie Honan. DNA Info. May 31, 2017.

“The Bugs That Changed Human History” by Mary Beth Griggs. Popular Mechanics. July 13, 2011.

“The Bugs That Bugged the Colonists” by David Robinson. Colonial Williamsburg Journal. Autumn 2007.