Homing in on Bed Bugs

Experts at NC State just won’t rest comfortably until they’ve shed light on bed bugs.

They’ve trained inspectors in workshops, brought in bed bug-sniffing dogs, demonstrated heat treatments and started studying the genetics of pesticide-resistant bed bugs.

Portable Pest

More international travel and less routine pesticide use have opened the door to infestations of bed bugs, said Dr. Mike Waldvogel, an Extension entomology specialist.

This generation of bloodsucking pests isn’t the stuff of nursery rhymes. Many bed bugs are resistant to common pesticides, making them tough to eradicate.

Waldvogel and other leaders at a recent workshop stressed the importance of getting professional help with a bed bug infestation.

Learn more and watch a bed bug-sniffing beagle.

Starting from Scratch

For the past four decades, bed bugs have posed few problems in the United States, said Dr. Coby Schal, urban entomologist. Research on bed bugs ceased in the 1950s as DDT and other powerful pesticides largely controlled the populations. Today’s entomologists are essentially starting from scratch.

Schal’s lab maintains bed bug populations for research. Colonies from across the U.S. share a very high resistance to pyrethroid-type pesticides. Schal suspects this generation of pesticide-resistant bedbugs may have descended from populations in Africa, Southeast Asia or South America, where pyrethroids are used in bed nets that protect against mosquitoes.

Using DNA extraction, researchers have found two genetic mutations related to pesticide resistance in U.S. bed bug populations.

Tracking the Spread

Scientists are using other genetic tools to “fingerprint” bed bugs to suggest how they colonize buildings and rooms. Schal’s group, in collaboration with population geneticist Dr. Ed Vargo, determined that a bed bug infestation in a 10-story building was so genetically similar that all the bugs likely came from a single source.

“An entire infestation could be founded by one pregnant female,” Schal said.

Researchers working on the bed bug problem include Schal and Vargo, as well as post docs Dr. Warren Booth and Dr. Alvaro Romero, who is working under a National Science Foundation fellowship. Assisting are doctoral student Virna Saenz and research specialist Rick Santangelo.

Romero’s work includes investigating the human scents that attract bed bugs, along with the body heat and carbon dioxide that we exhale. Such information could lead to potential “scent-based” traps that keep the bed bugs from biting.