Don't let them bite

Bed bugs are on the rampage again, despite their having been almost eradicated in the built environment. Now, John Clark of the University of Massachusetts Amherst and colleagues there and at Korea's Seoul National University have discovered how these tiny creatures, particularly those in New York City, have developed resistance to the pyrethroid neurotoxins, specifically deltamethrin, that once kept them in check. A genetic mutation that affects the animals neural membrane sodium channels means that these proteins are no longer a target for deltamethrin. In the city that never sleeps, some bed bugs are 264 times more resistant to deltamethrin than non-mutant strains. The research provides new clues for developing novel pesticides.