Man’s inept struggle against that tiny and most annoying of all pests, the bedbug, took a turn for the better this month with a report of a clever new way to knock the little guys off. Not a minute too soon either—it seems like they’re everywhere. Reports of infestation in New York City number in the tens of thousands, and getting rid of them can cost thousands of dollars.
After several millennia of trying without success to stomp, burn, and fumigate them out of our lives, researchers adopted a new strategy. Why not, they figured, seduce rather than repulse, entice rather than exterminate, lure them from their lair by exploiting their most basic impulse—blood lust.
The investigators ingested a medication called ivermectin, approved decades ago to treat various parasites and worms, and then exposed themselves to a swarm of bedbugs. They knew of course that the bugs, like any frisky vampire, could not resist the offer of warm human flesh; after all, bedbugs live on our blood. Right on cue, the insects hurried to the arm, bit down, had a nice blood meal—and dropped dead. The medication in the research volunteer’s bloodstream, though too weak to affect the human, was more than strong enough to kill the ambushed bedbugs.
This tactic of using people as bait is a radical paradigm shift in our dealings with pests and disease. Up to now, our approach to disease control has been the exact opposite—avoid and then avoid some more, be it with insect repellent, hand-hygiene products like Purell, or just steering clear of the guy over there who’s coughing so much. But with this advance, we are the cheese on the mousetrap, the ground beef spiked with rat poison, inviting the enemy in and imploring it to attack us. The humble bedbug appears to have turned 21st-century medicine on its head.
The excitement over this new approach is well deserved, but the glorious moment won’t last forever. Ivermectin, today’s wonder drug, also was approved in lotion form by the Food and Drug Administration earlier this year for that other urban scourge, head lice. After years of being used in the U.S. only for oddball infections (though it’s critical in combating the global scourge of river blindness), ivermectin will likely enter the fast lane of antimicrobials, with all the attendant overuse that the status implies. For the great paradox of antimicrobials is this: the more one is used, the faster bugs develop resistance. And as humanity’s long battle against bedbugs shows, the pests are nothing if not resistant.