Posted on 10/23/2011 7:15:22 AM PDT by PJ-Comix
Until about a decade ago, most people in the United States only knew about bedbugs through the seemingly dated phrase "Sleep tight, don’t let the bedbugs bite." But the bloodsucking parasites, which were largely eradicated by the mid-20th century, have roared back in all 50 states, and the bugs’ evolving resistance to insecticides is part of the reason for their resurgence. A new study gives the most complete picture so far of the adaptations some bedbugs have developed to thwart exterminators’ poisons.
The pesky bugs, it appears, can pump out a stew of enzymes that destroy insecticides, according to the study out this week in the journal PLoS ONE. This newly described neutralizing mechanism is in addition to a mutation, which scientists revealed a few years ago, that alters the structure of bedbugs’ nerve endings and prevents common insecticides from binding to their nerves. Together, these defenses could form a one-two punch that protects bedbugs from exterminators’ chemicals.
"The enzymes we discovered in the context of this paper are essentially the initial line of defense in breaking insecticide down before it reaches the nerve," Zach Adelman, lead author of the paper and an associate professor of entomology at Virginia Tech, says.
To figure out bedbugs’ defenses, Adelman and colleagues started by gathering a sample of bedbugs from Richmond, Va. The Richmond bugs had demonstrated strong resistance to a class of insecticides known as pyrethroids—the agents of choice for exterminators. Pyrethroids paralyze bedbugs by keeping open the sodium channels where nerves meet and communicate with one another. "The nerve will keep firing, and it can’t relax," Adelman explains. The result: paralysis and eventual death.
The researchers also used some bedbugs that had been reared in a lab in Fort Dix, N.J., for decades, and had not been exposed to chemicals. When Adelman’s team blasted both sets of bedbugs with two different pyrethroid insecticides—one called beta-cyfluthrin and another deltamethrin—they found that the Richmond bugs could withstand 111 times the dose of the beta-cyfluthrin insecticide compared with the Fort Dix bugs, and a whopping 5200 times the dose of deltamethrin.
Clearly, the hearty Richmond bugs had adapted some strong defenses. Adelman and company found that the bugs possessed one of the two mutations in genes coding for their sodium channels that researchers had previously seen in populations of New York bedbugs that were also resistant to this class of insecticide. The mutation is analogous to camouflage—it’s as if the insecticides can’t recognize the nerve endings they typically target. Adelson’s group also saw that the Richmond bugs were producing far higher levels of suspected insecticide-busting proteins in the cytochrome P450 monooxygenase and carboxylesterase families.
With these identifications, Subba Reddy Palli, an entomologist at the University of Kentucky, thinks the study will help in bringing bedbugs to heel. "This paper is good progress toward understanding insecticidal resistance," he says.
Now that his team has identified the genetic sequences bedbugs use to make these detoxifying compounds, Adelman says scientists can check populations worldwide to see how far this defensive capability extends. That will be important for establishing surveillance of growing resistance, as well as for creating new strategies for controlling the critters. For example, he says, if it seems that only the Richmond bedbugs have the genetic mutations needed to crank out this particularly powerful cocktail of enzymes, exterminators should engage in an all-out assault to try to wipe out that bedbug population before it spreads.
The arms race against bedbugs and other insects mirrors the battle with bacterial "superbugs" that have developed antibiotic resistance, such as those that cause staph and tuberculosis. Indeed, bedbugs have a long history of developing defenses against our chemical warfare agents. Bedbug "superbugs" first emerged in the 1950s. DDT (which was banned in 1972 because of human health concerns) wiped out most native bedbug populations in the U.S. by 1950. But some bedbugs survived, developing resistance to it, and later, organophosphate insecticides such as malathion.
Now pyrethroids are losing their effectiveness. "We have all these bedbugs we’ve chased from one chemistry to another," Dini Miller, a co-author of the study, an urban-pest management specialist for the state of Virginia, and a professor at Virginia Tech, says.
Yet the identification of bedbugs’ enzymatic countermeasures could ultimately provide exterminators with fresh ammunition. Besides insecticides, exterminators use a range of methods, including cold air, steam, and vacuums. But these repeated treatments can add up to hundreds or even thousands of dollars. Rejiggering conventional insecticides might still do enough damage to keep bedbugs at bay. "We can look at formulating things in new ways and get better penetration into these bedbugs," Miller says.
Down the road, scientists can base next-generation insecticides on chemicals substantially unlike those that bedbugs have already mastered disarming. Adelman says: "We can come back to the bugs and say, ‘We have a chemical you can no longer deal with given your arsenal. Now try this on for size.’"
New offensive weapons can’t come too soon, as the spread of these brownish or reddish bloodsucking insects has residents of heavy-hit urban areas such as New York City on edge. "Bedbugs don’t kill you," Adelman says, "but they can drive you crazy."
Can’t they do something to their little peckers so they can’t multiply?
I think they have done that with other insects.
LOL! So when the limousine liberals walk through Zuccotti Park to show their sympathies for the OWS protesters, they will probably end up bringing bedbugs home with them. It is quite a problem already in Manhattan.
Excellent way to put it!
Actually, that scenario just makes me chuckle. Bedbugs carried to a new home via a limo!
Keep your suitcase on the stand ... not the floor.
Check under the sheets along the corners of the mattress for shed skins and black spots. Also, behind the head of the bed... if you can.
In addition.... there’s a site, I think ... that tells you where people have reported bedbugs.
Same as bacteria and viruses that have less "sophisticated genes" have mutated through time? It's getting close to where anti-biotics will no longer work.
Hahahahahahahahahahahahahahahahahaha
Or worse! Maybe some lice, fleas, TB....
I agree with you Winstons Julia.
To say you get bedbugs from being filthy (especially since they don’t eat filth, they eat BLOOD, these aren’t cockroaches, you know?) is like saying you get lice because you don’t wash your hair.
Uneducated people is all. Not knocking them, but hate the judgmental snarks when they don’t have a clue what they are talking about.
Internet
I hate staying in hotels. I much prefer camping. Otherwise, I’d rather stay home and take day trips. Mr S gets impatient with me, but when we stay in a hotel, I’m always pulling off the bedding, checking the edged of the mattress, etc.
I’m predicting a Bedbug Collective (or Committee) to form at Zuccotti Park to deal with the problem of bedbugs in the near future. Maybe they will have to burn all their sleeping bags.
I know people who have used food grade Diatomaceous Earth. It is dangerous to critters with an exoskeleton.
Have them in my apartment now. Going through the third treatment. They come in through cracks, wall light and electrical sockets vents. If your neighbors have them...you will too. I haven’t slept in a bed for months now.
Sorry, but I couldn't help but laugh.
First thing that came to my mind is we can give them all vasectomies!
Let's see. Your screen name is PJ-Comix, so I hope you're just being funny or sardonic. Otherwise, I'd be amazed at how uneducated and/or clueless you are about the world around you.
My husband travels for his job. When he gets to the hotel room, he searches for the little devils. He will literally pull up the mattress and look under it. He will look in between any cracks and always behind the bed. Thus far... he hasn’t found any but one can’t be too careful. Even some of the high price hotel rooms have them. Oh yeah, when you enter the hotel room.. place your suitcases on top of the dresser before searching. It isn’t a guarantee but they are more likely in the carpet area than on top of a wood dresser.
BTW there is a very effective and nontoxic bedbug killer out, an active enzyme agent marketed as Bug-e Spray. Another brand is ERADICATOR.
They work by dissolving the bugs enzymatically on contact. No immunity possible. It also helps preventatively. Indispensible for staying in hotel rooms. You can buy it online. Oh yes, it also kills ticks and fleas and other bugs and is safe for pets.
Oh you vicious homophobe!
LOL That wasn’t intentional but I did think that might bring some funny replies just as I hit the post button.
I didn’t comment to ding anyone. Many people just are ignorant of what bedbugs are. They aren’t roaches.
They don’t go after “unclean” people ... they just want blood.
When I got them, my apartment complex told me not to make a big deal and there was no reason to go to the media...etc....
I think I probably got them from the library, because I frequented it and I noticed one day that THEY had changed out their upholstered chairs.
Really ... I think that if a place gets them ... they should be honest about it.
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