[Bed Bug Supplement] Battling Resistance

Pyrethroids have long been the go-to chemistry for quickly knocking down bed bug populations. But today, many bed bug strains are increasingly resistant to this conventional approach. In some cases, bed bugs’ exoskeletons can reduce the penetration of the insecticide. Other strains have more effective enzymes that break down the chemical once inside the insect’s body. Regardless of the source, this widespread resistance has made pyrethroid treatments unreliable as a stand-alone solution.

PMPs need control methods with new modes of action. One option is products that contain the active ingredient chlorfenapyr, which disables an insect’s ability to produce energy. Chlorfenapyr is a non-pyrethroid chemistry that becomes active as the bed bug metabolizes it. As the bug’s body breaks down the insecticide chemical, the pest grows tired and dies.

Until recently, insecticide treatments for bed bugs have mostly been curative (i.e., to control an existing infestation). This process often begins with an inspection and vacuuming and other mechanical means of quickly removing exposed bed bugs. Then a direct-contact insecticide treatment is applied, followed by spot treatments of a residual insecticide.

But, according to research published by the University of Kentucky, bed bugs tend to avoid areas where pyrethroid insecticides have been used. Resistant bed bugs survive and move away from pyrethroid treated surfaces, which may eventually cause the infestation to spread to untreated harborages.

If PMPs end up with three or more retreats when using pyrethroids as the primary treatment material, they should evaluate their application technique. Sometimes, the problem is a resistant population, which calls for a switch to a non-pyrethroid material or other adjustment to the control protocol.

Figure 1: Efficacy of Phantom SC termiticide-insecticide residual deposit on two surfaces on two pyrethroid-resistant bed bug strains during University of Kentucky study by Drs. Haynes and Potter. Masonite data not shown.

Prevention is a new reality. Eliminating a significant population requires extended exposure to a dry pesticide residue in harborage areas and the smart approach is to be proactive and start with a nonrepellent foundation such as products containing chlorfenapyr. Utilization of multiple classes of chemistry is also important to avoid the problems associated with resistance.

Phantom termiticide-insecticide has demonstrated residual control of resistant bed bug strains on various substrates (mattress fabric, medium-density fiberboard and masonite) during a recent University of Kentucky study (see Figure 1 above). Additionally, University of Minnesota research showed a near exponential increase of chlorfenapyr uptake by bed bugs the longer the interval between application and exposure (see Figure 2 below) for Prescription Treatment brand Phantom Pressurized Insecticide.

Other non-repellent solutions to consider are Prescription Treatment brand Alpine Dust Insecticide and Prescription Treatment brand Alpine Pressurized Insecticide, which contain dinotefuran. This active has been granted Reduced Risk status for public health use by EPA. (Author’s note: Prescription Treatment brand Alpine dust features the non-repellent active ingredient dinotefuran, which has been granted Reduced Risk status for public health use by the EPA.) This makes it a great product line for bed bug prone areas, even in sensitive accounts. Alpine Dust Insecticide and Alpine Pressurized Insecticide have both demonstrated excellent residual activity on a variety of surfaces for bed bug control.

The BASF Proactive Bed Bug Treatment Protocol recommends splitting treatment areas into likely (primary) and less likely (secondary) areas of bed bug infestation. Primary areas include headboard, cleat, mattress, box spring, frame and luggage rack, while secondary areas are curtains, outlets, chairs, dressers and baseboards. Using chlorfenapyr- or dinotefuran-based products as foundational non-repellents — pest management professionals should treat primary areas every six months, while secondary areas should be treated once every 12 months.

Figure 2: Increase of chlorfenapyr uptake by bed bugs using Phantom Pressurized Insecticide residual deposits on filter paper during University of Minnesota study by Dr. Kells.

Benefits of Prevention. Incorporating the BASF Proactive Bed Bug Treatment Protocol of using non-pyrethroid chemistry like chlorfenapyr and dinotefuran can:

• Reduce customer complaints, litigation and “down time” for hotel rooms.
• Provide an effective and economical treatment option with two applications per year (fewer re-treats, etc.).
• Limit human exposure compared to curative treatment methods (BASF protocol utilizes Crack & Crevice, spot and void treatments).
• Help control other pests (ants, cockroaches).

Long-lasting residues from the foundational non-repellents in the SmartSolution for bed bugs from BASF Pest Control Solutions effectively kills pyrethroid-resistant and nonresistant bed bugs. And because they are nonrepellents, they won’t cause bugs to disperse. Plus, the SmartSolution simultaneously employs multiple active ingredients, so PMPs avoid resistance problems.
 

The author is a market development specialist for BASF Pest Control Solutions.