They're small, blood-sucking parasites perhaps living in the corners and crevices of our beds, feeding off us while we sleep.

Bed bugs, for decades, existed as myths, part of a rhyme our parents told us before bed. Now they've made an unwelcome return and those who know the buggers best say it's high time we start taking them seriously.

After all, getting a bed bug infestation "is a bit of a crap shoot," conceded University of Kentucky entomologist Michael Potter, meaning all of us are at risk.

Bed bugs used to be "incredibly common" in the early 20th century, Potter said. Back then, people routinely checked for them and carried insecticide while traveling.

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But the introduction of potent insecticides killed most of our bed bugs, banishing them from our homes and consciousnesses. The bugs, Potter said, disappeared from about the mid-1950s to the late 1990s. They became so rare people could no longer identify them and a new generation of pest control professionals weren't equipped to fight them, noted University of Florida research scientist Roberto Pereira.

But then they came "roaring back in the last five to seven years," Potter said, creeping into our couches, our apartments and even into the hotel rooms of our NBA stars. The reason why is a mystery, although Pereira and Potter suggest it's because the once potent insecticide is now banned, people travel more and the bugs have grown resistant to modern insecticides.

Now we're left avoiding them. But there are ways. Here's what you need to know:

They're small and flat

If you've never seen one, bed bugs are small, flat, reddish-brown bugs about the size of Abraham Lincoln's head on a penny.

They have an oblong shell and a tiny head. They typically live in areas where people sleep because at night they feed on our blood.

Unlike ticks or fleas, bed bugs don't latch on when they feed. They bite then scurry away to digest. "It's a creepy parasite," described Potter. "It's a little bit like Dracula."