Don't let the bedbugs bite! (No, seriously.)

Most people in the United States associate bedbugs with nursery rhymes and Depression-era flophouses, and rightly so: originally brought to America by early European colonists, they're believed to have been more or less eradicated fifty years ago. But increasingly adventurous international travel by Americans and changes in pest control policies are now contributing to a resurgence in the bedbug population across developed nations -- so for the first time since the 1950s, it's more than just a saying: don't let the bedbugs bite, people.

Measuring only 2.5mm in width and able to flatten themselves into the tiniest of cracks and crevices, bedbugs can live in cracks in the wall and breaks in your mattress seam you didn't even know were there. They emerge at night, often just before dawn when sleepers are immersed in deepest REM. They're clever little buggers, too: attracted by the carbon dioxide you exhale and the heat that emanates from the fleshiest and easiest-to-slurp-blood-from parts of your body, they can attack in singles or in clusters -- some people have reported being bitten more than 500 times in a single night. (One sign of a serious bedbug problem? Anemia.) When they start feeding, they inject a tiny bit of anesthetic so you can't feel what they're doing and you don't wake up, and while they're at it they throw a little anti-coagulant in there too just to make sure all that yummy plasma flows freely. They can drink up to three times their own body weight in a single go.

Not only is it nasty -- it really happens. Two different couples I know each had to throw away all their mattresses, sheets and pillows when they found out they had bedbugs, get an expensive fumigation, and cross their fingers that the bedbugs didn't come back again -- something of a gamble, since the little suckers are increasingly developing inconvenient immunities to some forms of bug poison.

If you're really bug-phobic, you might want to skip this video from National Geographic -- but it's fascinating to actually see the bedbugs at work; they're usually so small and stealthy, most of us never actually see our many-legged adversaries in action: