Bed Bugs’ Genes Resist Pyrethroid Pesticides

At a recent meeting of the American Chemical Society (ACS), research was presented about bed bugs’ unique genetic defenses to common pyrethroid based pesticides.

Pyrethroid based pesticides are the most common pesticides used. And for quite some time, there have been many reports of real world (as opposed to laboratory grown) bed bug populations which have developed resistance to this class of pesticides.

At the ACS meeting, researcher Fang Zhu discussed finding 14 genes in bed bugs that help them survive pyrethroid pesticides. This genetic defense consists of two layers.

The first layer of defense is in the outer shell of the bed bugs, in which genes do such things as produce substances that alter the pesticides rendering them harmless and create a biological pump that expels the pesticides back out, before it can reach the body.

If pesticides slip past the shell, then the second layer of defense kicks in and consists of genes which do such things as prevent the pesticides from affecting the nervous system.

This explains why certain bed bug populations can survive 1000 times the normal dose of pyrethroid based pesticides.

At ZappBug, we have long advocated avoiding pyrethroid based pesticides. We only recommend non-pyrethroid pesticides, but it’s important to remember that pesticides alone (no matter how effective) are not enough to fully eliminate an infestation. We discuss at length the pros and cons of pesticide use here.

Aware of the limitation of pesticides, Zhu said: “In the future, efficient bed bug management should not rely on any single insecticide. We need to combine as many chemical and non-chemical approaches as we have to get rid of any infestation.” Zhu talked about using pesticides combined with other measures such as frequent vacuuming, washing and drying bedding on high heat, and sealing cracks and crevices to eliminate bed bug harborages.

For a long time at ZappBug, we have been advocating these steps and more, in a mult-pronged approach to eliminating bed bugs. For full details see our 8-Step Approach.

Posted by Andrew Havlis