5 Creepy Facts About Bedbugs They have a smell...that comes from their feces By Evann Gastaldo, Newser Staff Posted Jul 31, 2010 9:29 AM CDT 13 comments Comments In this undated photo released July 24, 2001, by the University of Florida, a common bedbug is engorged with blood after feeding on a human. (AP Photo/University of Florida, File) (Newser) – Bedbugs are back in a big way, with infestations closing at least two stores in New York City recently. AOL News lists five things you should know about these creepy crawlers: They smell: If you can smell their sweet, musky scent, chances are you’ve already got an infestation on your hands. Even grosser: The scent comes from their feces. They’re healthy: At least, their immune system is—they’re the only known insects with a specialized immune organ, so good luck getting rid of them. They can be useful: Since they feed on human blood, bedbugs at the scene of a crime can offer DNA evidence. For the complete list, including more than you wanted to know about their kinky sex practices, click here.