Bed Bugs Appear to Be Evolving to Resist Pesticides

Bed bugs have developed a genetic mutation that has made them resistant to our deadliest insecticides, according to a new study from researchers at Virginia Polytechnic Institute and State University. The same creatures that nibble on your flesh as you sleep are now nigh indestructible.

Researchers cracked open the DNA of the most common type of bedbug, the Cimex lectularius, and found the same gene mutation that makes German cockroaches immune to dieldrin, an insecticide used in chemical warfare that was banned in the 1970s. The gene in question, known as A302S in the Rdl gene, alters the bugs’ nervous system just enough to shrug off common insecticide sprays.

Pest control companies from across the U.S. and Canada handed over their grossest samples from 134 bed bug populations. Turns out, two of those populations were thriving as the researchers found that the mutation was in every single member of their population. The mutation may have been festering there for decades.

Researchers only had to genetically screen one bedbug from each population since, it turns out, bedbugs are not genetically diverse because they are very inbred. But, just to be sure, once the researchers found two bugs with the mutation, they went back and screened all of the bugs they had from that population and found that all of them had the same mutation that made them resistant to Dieldrin.

Dieldrin may be gone, but its modern relative, fipronil, has a similar structure and is in all kinds of pesticides, including your pet’s anti-flea medication. And these stubborn bugs are immune to that, too. This leaves scientists wondering: Is this a new mutation born from our ongoing chemical warfare, or is it an ancient gene that is, for some reason, just now awakening?

These are questions that will probably be answered years down the line after many more rounds of studies. All we know for sure is that if you want to get rid of your bedbugs, pesticides are pretty much a waste of money, but setting your mattress on fire and laughing maniacally in its orange glow is free.