Bed Bugs are Growing Resistance to Insecticides, Study Finds
Bed bugs have grown resistant to a widely used type of insecticides called neonicotinoids, a new study reported. The researchers noted that if resistance continues to grow, exterminating the blood-sucking insects can become difficult.
For this study, the research team collected sample populations of bed bugs living in Cincinnati, Ohio and Troy, Michigan in 2012. The team exposed all of the bed begs to four different types of neonicotinoid insecticides.
The researchers compared these bugs' responses to the poison to two colonies of bed bugs that they had collected earlier. In the first colony, the bugs were kept in the laboratory for 30 years without being exposed to any kinds of insecticides. In the other colony, the bugs that were collected in 2008 in New Jersey had developed resistance to pyrethroids.
The team reported that for the 30-yeaar colony, it took about 0.3 nanograms of neonics to kill nearly 50 percent of the group. In the recently collected group of bed bugs, it took 10,000 nanograms to kill the same percentage of bugs. In the group of pyrethroid-resistant bed bugs, the researchers found that they showed some resistance to neonics even though they had never been exposed to this group of chemicals.
"The insects produce detoxifying enzymes, and they use them to detoxify and this is one of the mechanisms they might be using to counter the insecticide effect," Dr. Alvaro Romero, the lead author from New Mexico State University, explained to BBC News. "In this paper we found that the Jersey city and these other strains have elevated enzymes. This is one piece of evidence that we have that these might have a role, but we need to do more work."
The researchers noted that their study only focused on bed bugs from two states so resistance might not be widespread. Regardless, they stressed the importance of finding non-chemical alternatives to exterminate bed bugs.
"While we all want a powerful tool to fight bedbug infestations, what we are using as a chemical intervention is not working as effectively as it was designed to," researcher Dr. Troy Anderson, an assistant professor of entomology in the Virginia Tech College of Agriculture and Life Science said in a written statement reported by the Huffington Post.
The study was published in the Journal of Medical Entomology.