jump to navigation

The Return Of Bed Bugs – Smarter Ones January 13, 2010

Posted by Mrs Weird Scientist in Animals, Evolution, Insects, Tough Stuff.
Tags: , , , ,
10 comments

Your mattress may be home to more than your pillow or favorite stuffed animal. It could be the home of bed bugs!

The title reads like a horror movie but for those who have battled it out with bed bugs, it makes a lot of sense. Others might think that ‘don’t let the bed bugs bite’ was just some bedtime line their parents used as a cute joke.

In fact, let’s see now who knew that bed bugs really existed. Try out the poll below (be honest!).


Bed Bug Basics

Bed bugs are small, reddish brown insects that feed on human blood, which engorges them and makes them bigger. They are from the insect family Cimicidae and common bed bugs are formally called Cimex lectularius. They tend to be most active at night, coming out of the cracks in walls or bed frames and other hiding places to get their bloody grub. They can travel in suitcases, so hotels are a hot spot for bed bugs as well as other places that see plenty of people coming and going. Cornell University has an ace fact sheet to give you the lowdown on bed bugs. You can also have some fun playing around on Pest World for Kids, a website created by the National Pest Management Association (NPMA). But let’s get back to finding out why these wee pesky critters have returned and what makes them smarter today.

Gone But Not For Long

Here we have a bed bug hiding in a wood bed frame. The bed bug looks like it's having a Sunday snooze but I bet it's getting rest so it can hunt for fresh blood! Image credit: Thomas Oldani

Bed bugs were once nearly destroyed in our modern environment, where the use of chemicals such as dichlorodiphenyltrichloroethane – otherwise more easily known as DDT – kept these beasties at bay. DDT is a pesticide that is either very useful or very toxic, depending on who you ask or what journal study you read. Ultimately though, it was banned.

The Good And Bad Of DDT

DDT was used to keep mosquitoes under control, mostly because they spread malaria. It was used to keep lice numbers down too. So what happened when it was banned? As somewhat of a side effect of its use, DDT had kept bed bug numbers down. After it was banned, a bunch of other chemicals were used to treat bed bug infestations. The bed bugs, however, got smart and developed resistance to some of these chemicals. That resulted in a big UH OH for society as bed bug infestations are now on a major rise! Scientists from the University of Massachusetts Amherst and Korea’s Seoul National University decided that it would be important to find out more about resistant strains of bed bugs in New York. The work was published in the Journal of Entomology. Let’s see what they discovered, shall we?

When researchers got busy observing bed bugs in New York, they found these pests had mutations in their nerve cells. What does this mean? It means they are resistant to the chemicals used to kill them. Where the chemicals would previously have paralyzed and killed the bed bugs, the mutations mean that bed bugs are now outsmarting their opponents – us!

Let The Bed Bug Collecting Begin!

To get the scoop on bed bug resistance, researchers took a sample of easily controllable ones from Florida and compared these to ones from New York that were harder to deal with. So just how resistant were these little bugs?

Look at this partially engorged bed bug. It probably looks similar to the bed bugs in Milan after they feasted on my blood. Oh, and a fun fact of the day: the Italian word for bed bugs is cimice dei letti.

Researchers found that the bed bugs in New York had up to 264 times the resistance to the modern chemical used to kill bed bugs – deltamethrin. If we picture a nerve cell, it has these little sodium channels on the outer membrane bit. This is where the flurry of nerve impulses come to life. In the New York bed bugs, this nervous system mutation means they can keep feeding long after those Florida ones have been exterminated.

Grossaroo

When I was in grade 3, I made up the word ‘grossaroo’ to describe anything yucky. This word is fitting in the case of what happened to me recently when I was working at an agency in Milan. After a few nights at what seemed to be a nice corporate flat, I began to get loads of itchy, inflamed red bites. I awoke one night to find a flattened-looking bug moving across my otherwise clean, crisp white sheets.

I yelped and quickly squished it with my slipper, only to see it turn into a smattering of blood, which it just took from its recent feeding of my body! Just after, I saw another one. By morning, my bed looked like a crime scene with all those splats of blood and bugs. Eeek! Fortunately, I got moved to a new place and had everything washed. Hopefully, those Milan bed bugs weren’t too hard for the building owners to get rid of, unless they’re resistant beasts like those New York ones.

Bed Bug Warrior To The Rescue

So now you know (if you didn’t already!) that bed bugs do exist. Not only that, but they’re continually evolving to get smarter, doing so in ways that make it harder to get rid of them. For now, you can be smart by being extra cautious when traveling. Always check for signs of bed bugs around the mattress and furniture. Since not everyone shows bites from these little pests, prevention will remain the best line of defense. And while it’s not necessarily smart, it sure is fun when checking for bed bugs to yell “YOU’RE GOING DOWN!” If your parents ask what you’re doing, you can explain that you’re the self-appointed family warrior here to protect everyone from bed bugs.

Image credits: Unless otherwise specified, images courtesy of the National Pest Management Association.

%d bloggers like this: