Associative learning turns DEET from aversive to appetitive in Aedes aegypti (journals.biologists.com)
65 points by croes 3 days ago
exabrial an hour ago
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).
gobdovan 10 hours ago
In plain English, they made mosquitos like repellent.
Y-bar 10 hours ago
Tldr: Repelln’t.
fooqux 44 minutes ago
I couldn't tell from the paper, but perhaps I missed it. Is this learned behavior hereditary?
zeafoamrun 10 hours ago
Could this already be happening out in the wild?
cactusplant7374 4 hours ago
I use a lot of bug spray and I am still swarmed sometimes.
fooqux 2 hours ago
As I understand it, DEET just prevents biting as they don't like the taste of it, and they taste with their feet. Thus, it doesn't do much to prevent initial attraction.
Edit: thought I'd include a link to a study about this as it's not well known. https://www.cell.com/current-biology/fulltext/S0960-9822(19)...
exabrial 2 hours ago
OutOfHere 9 hours ago
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.
GuB-42 an hour ago
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.
Foobar8568 8 hours ago
A couple years back, I spray some DEET on my shoes, 5 seconds later, a tiger mosquito tried to bite me on that spot (and yes on the shoe itself, just insane to see it trying ).
They already loved that shit.
cbdevidal 8 hours ago
Spray made from lemon eucalyptus works[1]. Not as well as DEET, but it works.
[1] https://www.consumerreports.org/health/insect-repellent/oil-...
cbdevidal 3 hours ago
I don’t understand why sharing an objective study with good news would be downvoted, someone please explain?
I’m not saying you have to use it; it’s good news for people who have concerns about other chemicals. It works—less effectively, but it works.
“Repellants containing (..) oil of lemon eucalyptus have also been found to be effective.”[1]
[1] Iowa Department of Health, “Controlling Spread of West Nile Virus“ https://hhs.iowa.gov/health-prevention/providers-professiona...
OutOfHere 3 hours ago
exabrial an hour ago
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.
OutOfHere 23 minutes ago
The parent comment was clearly not intended to replace DEET, only to add an oil that provides the missing repellent odor. The oil could intentionally be altogether useless for killing bugs for all I care. Even if DEET doesn't repel bugs, it's still intended to kill the bugs that intake it.
Also, the oils in question work reasonably for bug control, just for a lesser duration, requiring more routine reapplication. When you say they do not work, that's true only for the gap between how long the oils work versus how long ≥35% DEET works. And the concentration matters for both.
alwa 4 hours ago
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!
plmpsu 6 hours ago
Yeah, I would not be surprised if this learned behavior is passed on epigenetically. This is almost like gain of function research potentially.
AyyEye 9 hours ago
At that point just skip the deet.
trhway 10 hours ago
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 :)
HPsquared 8 hours ago
A bit like how capsaicin was evolved to prevent things being eaten by mammals, but... Well.. humans came along and developed a taste for it.
"Evolution! Can you give me capsaicin, to deter mammals? I want birds to spread my seeds!"
tardedmeme 6 hours ago
They got the ultimate seed-spreading, since we farm them.
adynaton 5 hours ago
Damn, were you working at Tselinoyarsk?
MiracleRabbit 9 hours ago
Freshly marinated in DEET
raverbashing 7 hours ago
So maybe the solution is to apply DEET to a bug zapper
neves 3 hours ago
It was fun, but not a bad idea. Are there mosquito mousetraps, or mosquitotraps?