The answer is just to use Picaridin instead of DEET, or perhaps a combination of both. Picaridin is sold as "Off - Clean Feel" or in Sawyer products in the USA.

The exact mechanism is not completely understood, but it's thought that DEET works because it interfere's with mosquitos ability to locate their prey. It is not thought to discourage bites as "they don't like the taste", just by interfering with sensing.

A newer repellent, Picaridin, not only interferes with locating prey, but actively deters mosquitos like pepper spray mace. It's an engineered molecule, derived from a compound called piperine, a substance found in black pepper plants.

Studies show that "Picaridin is as effective as DEET", but my personal experience is it is about twice as effective as DEET.

I spend an enormous amount of my free time outdoors and I can attest that Picaridin is far more effective than DEET for both mosquitos and ticks (we have two main species in the Kansas/Missouri/Arkansas region, others are present but less common).

As a personal data point, I had a friend trip on a hike this spring and fall into a grassy/bushy area. He did not put any repellent on. When we stood up, he was _covered_ in ticks. We got back to the truck and started peeling them off him, probably 15+ plus we flicked off or crushed. Unfortunately, we kept finding more, so we tried spraying Picaridin after the damn things hated that stuff so bad they jumped or fell off instantly.

You do not want to get Picaridin in your eyes or mouth, holy shit, that stuff is like bear mace. Also make sure you're downwind when you're spraying, your friends with appreciate that.

The other advantage of Picaridin is that it does not melt certain plastics. If you have life saving gear made of certain plastics, DEET can melt many times of plastics! (Notably some PVCs, polycarbonates, acrylics, acetates, and elastics).

In plain English, they made mosquitos like repellent.

that explains. I was always wondering why in Siberia (where i worked for 2 summers back then at university times) coming out from house with freshly applied DEET you're getting covered with mosquitos - i was attributing that to the especial ferociousness of the mosquitos there - yet it sounds like the smell of DEET for them in those towns may have become like a BBQ smell for us :)

If all they wanted to achieve was attract mosquitoes they could have just hired me to stand there for a few minutes. Very reasonable rates, guaranteed mosquito attraction or your money back.

But if what they wanted to achieve was to show how to make DEET ineffective then I hope their entire research department is proscribed as the terrorist organisation it really is by every nation on Earth.

I hope these mosquitoes were not released in the wild.

The simple answer would be to add a natural strongly repellent gentle oil to the DEET spray.

Maybe an effective answer would be to combine DEET with an insecticide.

Mosquitoes attracted to DEET will die because of the insecticide. Usually, for personal protection, we tend to prefer repellents, as we don't want to get bitten, killing the mosquito after the fact is not very useful. But here, the idea is to put some evolutionary pressure against mosquitoes not repelled by DEET.

There are also repellants other than DEET. Icaridin being the best alternative. It is almost as effective as DEET without many of its drawbacks. Some essential oils too, as you said, but I don't think any of them have the effectiveness of icaridin or DEET.

And remove the DEET from it, apparently… at least until it loses its appetitive charge.

Until, of course, they learn to like the replacement oil. At which point, break back out the DEET!

We ran into exactly this arms race problem with rodent repellents in a lab context. The rotation strategy actually worked pretty well -- swap compounds before habituation fully sets in. The tricky part is timing it right; you need some threshold of aversion to return before re-introducing the original. Otherwise you're just accelerating tolerance to both.

Yeah, I would not be surprised if this learned behavior is passed on epigenetically. This is almost like gain of function research potentially.

The epigenetic angle is interesting but I'd push back a bit. The paper specifically uses classical conditioning with sucrose reward, and the effect appears to dissipate across generations in the lab strains they tested. Learned valence without heritable reinforcement is pretty standard invertebrate behavior, not really gain-of-function territory.

At that point just skip the deet.

There are no natural oils that have been proven to stay effective, or are effective as DEET.

Go ahead, hose yourself down with Lemon oil, citronella, oil, or lemon eucalyptus oil. They simply do not work.

Lab study. They weren't released. That concern answers itself if you read past the abstract.

The oil additive idea has been tried since at least the mid-90s. Synergy isn't there -- you get an oily mess that degrades DEET's efficacy. Straight DEET still wins on duration.

Could this already be happening out in the wild?

I use a lot of bug spray and I am still swarmed sometimes.

I couldn't tell from the paper, but perhaps I missed it. Is this learned behavior hereditary?

It doesn't seem the case; the study was made purely on behavioral conditioning. And mosquitoes don't live very long, so it's unlikely they'd learn this in practice, outside of a very controlled environment.

But there's a natural selective pressure, and it's plausible that mosquitoes would eventually evolve their sensors to become attracted to DEET, over multiple generations. And with each generation lasting only 20-30 days and a single female mosquito laying 300-500 eggs in total, they can evolve orders of magnitude faster than us.

Hereditary in the Mendelian sense, probably not. But epigenetic transmission is a separate question -- some insects pass stress-induced methylation patterns to offspring. If conditioning during a blood meal could prime her eggs somehow... it's a stretch, but the mechanism isn't obviously impossible and I haven't seen it ruled out.

I always found DEET interesting because it is a toluene derivative, which is why it is remarkably effective at destroying plastics and such, in addition to being a repellant. Yet people spray it with abandon and then wonder what melted their watch or glasses or …

The behavioral vs. genetic distinction matters here. Acquired repellent tolerance through associative learning could spread through a population much faster than selection on receptor variants. Whether that actually happens in field conditions -- where DEET exposure isn't reliably paired with blood meals -- is an open question, but it seems worth considering when evaluating long-term efficacy assumptions baked into public health recommendations.

It's OK, we still have picaridin