ByKiley Price
Published October 10, 2023
• 8 min read
Fashion designers and celebrities recently gathered in Paris for Fashion Week, but they weren’t the only ones making headlines. Videos flooded social media and news channels of bedbugs crawling through the cushioned crevices of the city—from seats on the Metro to cinema recliners.
The insects have fueled widespread concern across Paris and the rest of the world due to the number of travelers in the city that could return home with a bloodsucking hitchhiker in tow. “No one is safe,” the first deputy mayor of Paris tweeted during Fashion Week.
Though bedbugs may be pesky, these insects do not spread disease and are typically more of an itchy nuisance than a severe threat to your health. They were largely absent from the 1940s to the late 1990s due to the use of pesticides, but they have made a resurgence in recent years, exploding in nearly every major city, including New York City and Hong Kong. The situation in Paris may not be an outbreak at all, but rather evidence of a longstanding issue—and an example of what makes these critters so effective.
“My guess is that they’ve had a bedbug problem under the scene for a very long time,” says Zachary DeVries, an urban entomologist at the University of Kentucky. “It didn’t just show up during Fashion Week. Somebody just happened to see it and drew attention to it … Right place, right time—or in their case, probably wrong place, wrong time.”
Anyone who has experienced a bedbug infestation in their own home knows that bites from these insects can cause itchy, uncomfortable welts. People likely also know how difficult it is to remove bedbugs once they get inside, nesting within the fabrics and cushions of furniture.
An individual bedbug usually only lives for a few months, or in some cases, up to a year. But that’s plenty of time for a population to explode, according to DeVries.
“You could drop a single female off in your home who has been mated and very quickly, she can start a population that can grow out of control in just a matter of weeks to months,” he says.
What are bedbugs?
Bedbugs are part of a family of insects called Cimicidae, which includes around 100 species of small parasitic bugs that feed on warm-blooded animals. Only three of these species typically bite humans, the most common of which is known as Cimex lectularius.
Adult bedbugs are ruddy brown, wingless, and roughly a quarter of an inch long—about the size of an apple seed. They are often confused with other blood suckers, such as fleas, but can be differentiated by their flat, oval bodies.
“Bedbugs have been a problem for as long as we have recorded history,” DeVries says. Their tiny remains have even been found in Egyptian tombs dating back more than 3,500 years. But where did they come from in the first place? Scientists aren’t yet certain of the earliest bedbug ancestors, but one of the leading theories for the emergence of modern-day bedbugs is that they evolved in association with bats.
“Some 200,000 years ago or so, when humans cohabited caves with bats, a lineage of bedbugs became associated with humans,” says Coby Schal, an urban entomologist at North Carolina State University. “As humans left the cave, though, that lineage followed.”
The appetite of a pest
Every few months for more than 35 years, Lou Sorkin has practiced the same ritual: He sits down at his kitchen counter, sips a cup of coffee, and feeds his bedbugs. A New Jersey-based entomologist, Sorkin has raised and studied these critters throughout his career, letting more than 200,000 bedbugs dine on his arm over the past few decades, by his estimates.
“It isn’t much of an issue because I don’t react badly to having been fed upon,” says Sorkin, who now works in a consulting business that helps people identify and treat pest outbreaks in their homes.
Before each feeding, Sorkin first exhales into the glass containers that hold the bedbugs behind a thin screen. Unlike cockroaches, bedbugs aren’t interested in sandwich crumbs or dirty dishes; instead, they are drawn to the carbon dioxide in your breath, the heat of your body, and your scent, including the smell of your dirty laundry, according to a 2017 study.
Once a bedbug finds its target, the insect jabs a needle-like tube that’s attached to its head into the skin to suck out warm blood. It also injects a flurry of proteins at the bite site, including a numbing agent and an anticoagulant to prevent the blood from clotting.
During a feeding, bedbugs can fill up with six times their weight in blood, often resembling “a Christmas ornament” by the time they are satiated, according to Schal. Though bedbugs are not known to carry disease, their saliva can induce an allergic response in some people, resulting in large, itchy bumps. Others might not even realize that they are living alongside bedbugs because their skin has no reaction at all, Schal says.
Proliferating parasites
Through a strategy known as traumatic insemination, an adult male bedbug will jab a female’s abdomen with his sickle-shaped penis and inject his sperm directly into her body to mate. The sperm passes through the female’s open circulatory system into her ovaries, where the egg is fertilized.
“The female has a fully functional genital tract that the male chooses to ignore and stab her in the side anyway,” says William Hentley, an ecologist at the University of Sheffield in England. “How it evolved is a bit of a mystery, to be honest.”
Over time, female bedbugs have evolved a specialized organ in their abdomen known as a spermalege that’s packed with immune cells, which helps prevent bacterial infections at the site of the wound. After this violent copulation, the female typically lays one to seven eggs per day, which hatch into nymphs. These nymphs go through five different stages of molting and growth, known as instars, before reaching adulthood, though they must consume a blood meal before completing each molt.
A common bedfellow
Throughout history, humans have made countless attempts to control bedbug outbreaks. One of the most successful efforts was during World War II, when the now-banned pesticide DDT was widely distributed to kill insects. This chemical was exceptional at tamping down bedbug outbreaks—at first. By the 1990s, a new population of bedbugs immune to the potent effects of DDT began to spread.
“This is the problem with pesticides because as soon as you start killing off loads of them, but leaving a few, resistance quickly evolves in a population,” says DeVries, adding that this is similar to diseases developing antibiotic resistance in the medical world.
Compounding the issue, global travel has grown in the recent decades, making it possible for bedbugs to spread across the world and find new hosts each day. As a result, bedbug populations have largely grown in this time, and many of the insects are now highly resistant to a variety of pesticides on the market. Exterminators often rely on heat treatments because bedbugs will die if they are exposed to temperatures above about 110 degrees Fahrenheit for 90 minutes or more.
“The best way to not get bedbugs is to buy a cabin in the woods and never leave and hide there, but then you miss out on all the enjoyment and pleasures in life,” DeVries says. “Don’t carry the paranoia around with you. It’s not going to help you, and at the end of the day, they’re just bugs and we can manage and deal with them at this point.”
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