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Associative learning turns DEET from aversive to appetitive in Aedes aegypti

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Re: Associative learning turns DEET from aversive to appetitive in Aedes aegypti

#31

Post by fooqux »

exabrial wrote: post #29
fooqux wrote: post #27

Earlier quoted context omitted.

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)...

I believe DEET interferes with their ability to locate prey actually.

There may be multiple ways it works, but we don't fully understand all of them. However, here is one study about the feet to show I'm not spouting AI generated bullshit: https://www.cell.com/current-biology/fulltext/S0960-9822(19)...

Re: Associative learning turns DEET from aversive to appetitive in Aedes aegypti

#32

Post by GuB-42 »

OutOfHere wrote: post #13

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.

Re: Associative learning turns DEET from aversive to appetitive in Aedes aegypti

#33

Post by exabrial »

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).

Re: Associative learning turns DEET from aversive to appetitive in Aedes aegypti

#35

Post by OutOfHere »

exabrial wrote: post #30
OutOfHere wrote: post #13

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.

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.

The parent comment was clearly not intended to replace DEET, only to add an oil that provides the missing repellent odor if this were to become a real issue. For all I care, the oil could intentionally be altogether useless for killing bugs. After all, even if DEET doesn't repel bugs, it still is 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 acutely for both.

Re: Associative learning turns DEET from aversive to appetitive in Aedes aegypti

#36

Post by YeGoblynQueenne »

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.

Re: Associative learning turns DEET from aversive to appetitive in Aedes aegypti

#37

Post by random3 »

exabrial wrote: post #33

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 ne…

That’s interesting! As I’m researching this (for my family) I have questions :) - have you tried entomol? How does it compare? - is it advisable with for young kids, if it’s irritant? - how long does it stay on? - what do you do when you get so many ticks on yourself? Watch if you get spots after 30 days?

Entomol is hydrogenated catmint oil

Re: Associative learning turns DEET from aversive to appetitive in Aedes aegypti

#38

Post by YeGoblynQueenne »

cbdevidal wrote: post #16
OutOfHere wrote: post #13

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.

Spray made from lemon eucalyptus works[1]. Not as well as DEET, but it works. [1] https://www.consumerreports.org/health/insect-repellent/oil-...

It works, as do other plants with strong, lemon-y smells (like citronella and geraniums) but the problem with those concoctions is that they don't last long. I've used them a lot in the past and at most they'll last an hour or so. Their problem as far as I can tell is that they evaporate quickly and once you can't smell them anymore nor can the mosquitoes, and you're fair game again.

DEET is so effective because its effects last a long time. In my experience it basically lasts until I wash or go for a swim, so for as long as it's on my skin. Granted, since I normally use it in the summer months when I'm likely to swim daily it doesn't last more than a day in practice, but that's already far longer than any of the plant-based ones I've tried.

Re: Associative learning turns DEET from aversive to appetitive in Aedes aegypti

#39

Post by exabrial »

random3 wrote: post #37
exabrial wrote: post #33

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 ne…

That’s interesting! As I’m researching this (for my family) I have questions :) - have you tried entomol? How does it compare? - is it advisable with for young kids, if it’s irritant? - how long does it stay on? - what do you do when you get so many ticks on yourself? Watch if you get spots after 30 days? Entomol is hydrogenated catmint oil

Never tried Entomol. But I've found any of the essential oils simply don't work more than 10-20mins after application. I'd be very skeptical, but I'll try it if I can find an EPA/FDA approved spray.

Picaridin is safe for everyone, but follow all label instructions. Also use the 20% concentration. I find that 10%-15% is about as effective as DEET, 20% is about twice as effective (in my completely uncontrolled, unscientific, testing).

Re: Associative learning turns DEET from aversive to appetitive in Aedes aegypti

#40

Post by exabrial »

OutOfHere wrote: post #35
exabrial wrote: post #30

Earlier quoted context omitted.

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.

The parent comment was clearly not intended to replace DEET, only to add an oil that provides the missing repellent odor if this were to become a real issue. For all I care, the oil could intentionally be altogether useless for killing bugs. After all, even if DEET doesn't repel bugs, it still is intended to kill the bugs that intake it. Also, the oils in question work reasonably for bug control, just for a lesser du…

Fair point. It could be a combination could possibly be an effective repellent. But the essential oils simply do not work by themselves.
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