"And don't let the bed bugs bite" is no longer a harmless adage. In reality today, these bloodthirsty bugs infest thousands of homes. According to a team of Penn State entomologists, biopesticides -- naturally occurring microorganisms -- might provide an answer to this pest problem. Bed bugs need blood meals for growth and development throughout their life cycle. Increased travel, widespread insecticide resistance and changes in management practices have caused a resurgence in those insects throughout North America and Europe. Compounding the problem are concerns about the safety of using traditional chemicals in the domestic environment.
According to Nina Jenkins, senior research associate in entomology, preliminary bioassays on the effects of Beauveria bassiana -- a natural fungus that causes disease in insects -- on bed bug control have been performed, and the results are encouraging. She and her colleagues report their results in the most recent issue of the Journal of Invertebrate Pathology.
Jenkins, working with Alexis Barbarin, a former Penn State postgraduate student now at the University of Pennsylvania, Edwin Rajotte, professor of entomology, and Matthew Thomas, professor of entomology, looked at how B. bassianaacts through contact with its insect host.
"They are natural diseases that exist in the environment," said Jenkins. "They are relatively easy to produce in a lab and stable, so you can use them much like chemical pesticides."
In the study, the researchers used an airbrush sprayer to apply spore formulations to paper and cotton jersey, a common bed sheet material. Then control surfaces, again paper and cotton jersey, were sprayed with blank oil only. The surfaces were allowed to dry at room temperature overnight. Three groups of 10 bed bugs were then exposed to one of the two surfaces for one hour. Afterward, they were placed on clean filter paper in a petri dish and monitored. The researchers found that all of the bed bugs exposed to the biopesticide became infected and died within five days.
Also, there were no prominent differences in susceptibility by feeding status, sex, strain or life stage. Most importantly, the infected bed bugs carried the biopesticide back to their hiding places, infecting those that did not go out in search of blood.
"We exposed half of a population of bed bugs to a spray residue for one hour and then allowed them to go into a harborage with unexposed individuals," said Jenkins. "The fungal spores were transferred from the exposed bug to their unexposed companions, and we observed almost a hundred percent infection. So they don't even need to be directly exposed, and that's something chemicals cannot do."
This result is important because bed bugs live in hard-to-reach places.
"Bed bugs tend to be cryptic, and they'll hide in the tiniest crevices," said Jenkins. "They don't just live in your bed. They hide behind light switches and power sockets and in between the cracks of the baseboard and underneath your carpet."
The speed of mortality with B. bassianais as fast as Jenkins has seen in any application, but it doesn't even need to be that fast.
"If you are trying to protect a farmer's field, he wants the insects that are eating his crop dead immediately," said Jenkins. "Obviously, if you have bed bugs in your house, you don't want them there for any longer than you have to, but what you really want to know is if they've all gone at the end of the treatment, and I think that's something that this technology could offer."
Next, the researchers will test the effectiveness of brief exposure times and look at entire populations where natural harborages are established. Then they will begin field work.
"It's exciting, and it definitely works," said Jenkins. "We're working on the next step, and we have more funding to support these studies."
Penn State: http://live.psu.edu
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
Volunteers in Sweden were tricked into thinking their bodies had vanished, and the "superpower" seemed to ease social fears
Scientists have for the first time captured how taste sensations are processed on the tongue
Researchers set hungry mosquitoes loose on identical and fraternal twins. They found that inherited genes do play a role in making you a mosquito magnet.
State education committee passes a bill banning parents exempting kids from vaccination because of "personal beliefs", as lawmakers around the world discuss similar measures
The torturous trial-and-error process of finding the best cancer drug for an individual could be a thing of the past thanks to a couple of clever devices
A flu strain deadly to chickens and turkeys is striking farms in the West and Midwest. This week, it hit an Iowa facility with millions of egg-laying hens. No one knows how it's entering houses.
Doctors, it turns out, often don't follow evidence-based guidelines. One result? Unnecessary tests. Scientists who study this contrariness think they know why.
Analysis of millions of audio files has led one US company to claim that their software can predict how a person’s voice will make a listener feel
Bird flu outbreak now spreading through Midwest poultry could head east with fall migration
A little MRI video seems to settle the decades-old debate about that loud pop of the joints: It's all about bubbles. But imagine an air bag inflating, not the bursting of a balloon.