Bed bugs, possessing mouths designed to pierce skin and suck, are exquisite at gulping blood meals.

These insects have sucked blood from frustrated human hosts for thousands of years, and recent viral posts on social media from Paris show the nuisance pests are continuing to successfully infest homes today. The pests have generally resurged worldwide in the last couple decades. For example, two of the largest universities in Mexico recently suspended school to contend with a bed bug outbreak. These recent infestations might leave you with questions about how problematic bed bugs are in modern times, how they spread, myths about bed bugs, and what you should do if, gasp, they find their way into your bed.

Bed bug experts answer all these questions below. It would benefit everyone to better understand these pests, because no one is immune from a bed bug infestation.

"You can be rich or poor, they don't discriminate," Alvaro Romero, a professor in urban entomology at New Mexico State University who researches bed bugs, told Mashable.

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And bed bugs, generally, aren't going away. They live where we live.

"They need us. They need to feed on us. We're the perfect host," Jody Green, an urban entomologist at the University of Nebraska–Lincoln who specializes in bed bugs, told Mashable.

"You can be rich or poor, they don't discriminate."

While bed bugs don't spread disease, their bites — red marks similar to mosquito bites that can form in a straight line or be randomly spaced — are unnerving, if not quite itchy. (Important note: Romero notes that about 50 percent of people do not show skin reactions to bed bug bites. So just because you don't have bites doesn't mean the bugs aren't there.)

Bed bugs gathered by the CDC from an urban hotel in Georgia. An arrow points at a nymph. Credit: CDC

How do bed bugs spread and travel?

Bed bugs commonly spread aboard infested items like luggage, clothing, and furniture, Romero explained.

These pests are excellent hiders. They can easily hitch a ride across the city, or world, in luggage.

A bed bug spotted on a bed frame. Credit: Alvaro Romero

What causes a resurgence or "invasion" of bed bugs?

We've set the stage for bed bugs to thrive, or have a resurgence, in many modern-day environments.

- Bed bugs succeed in urbanization: Some 55 percent of the world's population lives in urban places, a number that will climb to nearly 70 percent by 2050, according to the UN. These places, like Paris, allow bed bugs easy movement from place to place. "This high density facilitates mobilization and transportation of bed bugs," Romero said.

- Increase in domestic and international travel: Air travel is booming, and the industry is expected to grow significantly in the coming decades. This will allow bed bugs more opportunity to hitch rides on luggage or clothing.

- Insecticide resistance: Researchers continually find that bed bugs are growing resistant to pest control chemicals. This makes outbreaks more challenging to stop, or control.

"We predict that bed bugs are going to stay with us for a long time," Romero said. But we can take effective steps to keep them from spreading.

How to prevent bed bugs from spreading

Fortunately, prevention often works. "Early detection is key," Green said.

• Know what bed bugs, both adults and nymphs, look like (see examples above), Romero emphasized.

• Hotels are common places to get bed bugs. So after you check in, check around bedding areas in hotel rooms, particularly the headboard, a favorite bed bug hangout. Look for "fecal spotting" (dark spots left on material), roundish bloodstains (left by feeding bed bugs), and clusters of eggs.

• When returning home from a trip, be vigilant. "I can control what I bring home," Green emphasized. This means checking luggage for bed bugs and storing luggage away from bedrooms. Both dirty and unused clothing should be heated in the drier for 30 or so minutes. "Dry heat will kill all the life stages, including the eggs," Green noted.

Bed bug fecal spotting on furniture in Paris, France. Credit: Nathan Laine / Bloomberg via Getty Images

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What to do if you have a bed bug infestation

Romero suggests seeking pros.

"An effective control or eradication of bed bugs requires hiring a knowledgeable professional pest control company," he said. That's because it's challenging to eradicate bed bugs without seasoned experience. These insects are active at night and at times can be great at hiding from the unseasoned eye. Additionally, professionals know how to use insecticides, and where to apply them.

"They bite everybody."

Some people will try steamers to kill the furtive bugs with heat. This can help, but it might not eradicate your problem.

Pest control experts applying insecticide on a mattress in Paris, France, in October 2023. Credit: Nathan Laine / Bloomberg via Getty Images

Myths about bed bugs

There are quite a few myths. Here are some:

- Myth: Bed bugs can't infest clean places: Romero has found bed bugs in pristine-looking places, such as a nice hotel room in Cincinnati, Ohio. "It was the cleanest hotel room I've ever slept in," he said. Yet even there, bed bugs lurked.

"Bed bugs have been found in five-star hotels and resorts, and their presence is not determined by the cleanliness of the living conditions where they are found," the CDC explains.

- Myth: Vacating a home for a long period of time will get rid of bed bugs: Not so. Bed bugs can survive for three to four months without feeding, Romero explained.

- Myth: Bed bugs don't bite some people: "They bite everybody," Romero said. But around 50 percent of people don't have allergic skin reactions to the bites.

Stay vigilant out there, humans.