According to recent studies, bed bugs are building resistance to certain insecticides, making their demise increasingly difficult.

Researchers in the University of Kentucky College of Agriculture collected 21 groups of common bed bugs from various Midwestern cities and identified 14 molecular markers in the pests that allow them to be resistant to pyrethroid insecticides, a category of insecticide in some of the most common household bug sprays. Those genes protecting these pests were most prominent in the tough outer shell, providing a barrier for insecticides before reaching target sites on nerve cells, where an additional layer of resistance is common.

According to the research, this resistance strategy has evolved in bed bugs and is based on their unique morphological, physiological and behavioral characteristics. It has not been reported in any other insect species.

Click here to read the full results of this study.