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snowblind
02-22-2013, 11:11
http://www.bbc.co.uk/news/science-environment-21519998

Looks like it might be permethrin, long sleeves, and headnets from now on. Journal article within, goes more in depth.

Pathfinder1
02-22-2013, 11:40
Hi...


Yes, just saw this on another forum...thanks.

It's been years since I stopped using a repellent that (first hand experience) will dissolve paint, or 'melt' plastic (DEET). Don't want any of THAT stuff on my self...!!

Prime Time
02-22-2013, 12:01
They're mosquitos in a lab. I seldom apply deet but when I do, it works pretty well against mosquitos and black flies. I prefer hiking faster as my first line of defense. Anything over 3 mph is bug free. 2-3 needs some swatting. Under 2 and you're a sitting duck. Giddyup people!

Wise Old Owl
02-22-2013, 12:02
For a product that has been out there for 40 years as the only go to product that works in the wild this is no surprise, they are working on some 125 different products right now and are looking for a new combination.

ChinMusic
02-22-2013, 12:34
I cannot see mosquitoes having an evolutionary change because people use DEET. We are just not significant a food source for them. Now if ALL animals used DEET I could see it happening just as bugs becoming resistant to pesticides.

IMO this is not occurring in the wild.

Hairbear
02-22-2013, 12:44
Scientist have found that pest to agricultural crops are becoming resistant to agricultural sprays also. There is quite the concern for this.

Slo-go'en
02-22-2013, 13:18
Scientist have found that pest to agricultural crops are becoming resistant to agricultural sprays also. There is quite the concern for this.

That's a some what different situation, as the insecticide is used over large areas, affecting billions of insects at a time.

GoldenBear
02-22-2013, 13:55
First of all, it's not all mosquitoes -- only the species Aedes aegypti was tested.
Secondly, these mosquitoes are not "adapting" to DEET in some Darwinian manner, INDIVIDUAL MOSQUITOES simply learn to ignore its effects after several hours.

READ THE ARTICLE:
researchers from the London School of Hygiene and Tropical Medicine took some A. aegypti mosquitoes in the laboratory, and tempted them with a human arm covered in Deet.
As expected, the repellent put the insects off their potential meal.
However, a few hours later when the same mosquitoes were offered a chance to dine again, the researchers found that the Deet was less effective.

In other words, if you hang around the same group of a specific species of mosquitoes for several hours, the effect of DEET will wear off after a few hours (bizarre as it sounds, we really don't know WHY insects don't land on skin or cloth with DEET, we're just glad they don't).
Remember that there is no Darwinian advantage in being able to ignore the effects of DEET, as it does NOT kill mosquitoes -- DEET simply makes insects not land on the area with that chemical.
Mosquitoes that learn to ignore the effects of DEET are no more likely to survive than those who do ignore those effects. The latter insects simply fly over to mammals without DEET, gorge away, and reproduce.

The only thing this article notes is that the effectiveness of DEET decreases after several hours, if used against the same Aedes aegypti.
It does NOT say that:
- the effectiveness is becoming less when first used.
- it becomes ineffective after several hours.
- offspring of the ones that, after several hours, ignore the effects of DEET will also have this reaction.
- mosquitoes in North America share this ability to ignore DEET after several hours.

Last year at least 243 people in the U.S. died due to mosquito bites.
http://www.cdc.gov/ncidod/dvbid/westnile/surv&controlCaseCount12_detailed.htm
All of them would have survived had they been adequately protected with DEET.
Unless someone can convince me that 244 people died last year due to use of DEET, then I'll do the intelligent thing and use a product that protects me, better than any alternative, for hours.

Hodge Podge
02-22-2013, 14:33
Hang out at Assateague Island during a calm day and you can watch mosquitos land in a pool of DEET to bite you. Hence it is a repellant (deterrant) and not a proofing mechanism (like a net cabana or fire). Think of it akin to wearing camouflage--you may be harder to find, but once you are found...

Feral Bill
02-22-2013, 14:49
First of all, it's not all mosquitoes -- only the species Aedes aegypti was tested.
Secondly, these mosquitoes are not "adapting" to DEET in some Darwinian manner, INDIVIDUAL MOSQUITOES simply learn to ignore its effects after several hours.

READ THE ARTICLE:
researchers from the London School of Hygiene and Tropical Medicine took some A. aegypti mosquitoes in the laboratory, and tempted them with a human arm covered in Deet.
As expected, the repellent put the insects off their potential meal.
However, a few hours later when the same mosquitoes were offered a chance to dine again, the researchers found that the Deet was less effective.

In other words, if you hang around the same group of a specific species of mosquitoes for several hours, the effect of DEET will wear off after a few hours (bizarre as it sounds, we really don't know WHY insects don't land on skin or cloth with DEET, we're just glad they don't).
Remember that there is no Darwinian advantage in being able to ignore the effects of DEET, as it does NOT kill mosquitoes -- DEET simply makes insects not land on the area with that chemical.
Mosquitoes that learn to ignore the effects of DEET are no more likely to survive than those who do ignore those effects. The latter insects simply fly over to mammals without DEET, gorge away, and reproduce.

The only thing this article notes is that the effectiveness of DEET decreases after several hours, if used against the same Aedes aegypti.
It does NOT say that:
- the effectiveness is becoming less when first used.
- it becomes ineffective after several hours.
- offspring of the ones that, after several hours, ignore the effects of DEET will also have this reaction.
- mosquitoes in North America share this ability to ignore DEET after several hours.

Last year at least 243 people in the U.S. died due to mosquito bites.
http://www.cdc.gov/ncidod/dvbid/westnile/surv&controlCaseCount12_detailed.htm
All of them would have survived had they been adequately protected with DEET.
Unless someone can convince me that 244 people died last year due to use of DEET, then I'll do the intelligent thing and use a product that protects me, better than any alternative, for hours. Nice analysis. Thanks.

starbright
02-22-2013, 18:36
Deet works pretty good for me but my kids are allergic to it so we usually use Eucalyptus it works just as good.

Pedaling Fool
02-22-2013, 18:42
Nice analysis. Thanks.
I second that.

Pingus
02-22-2013, 19:11
DEET has always worked well for me. There has been no drop off in effectiveness these last few years. I'll still be using it and expect the same results. This study is flawed from many angles.

ChinMusic
02-22-2013, 19:14
DEET has always worked well for me. There has been no drop off in effectiveness these last few years. I'll still be using it and expect the same results. This study is flawed from many angles.

I agree. DEET is a known commodity that will perform just as well tomorrow as it did 30 years ago.

A/B
02-22-2013, 21:39
This is a pretty interesting idea, that seems to work. I plan on trying it this spring.

http://www.originalbugpatch.com/how-bug-patch-works

hikerboy57
02-22-2013, 22:06
This is a pretty interesting idea, that seems to work. I plan on trying it this spring.

http://www.originalbugpatch.com/how-bug-patch-works

vitamin b1 actually does work. alters your body chemistry so you dont smell good to mosquitoes. i used to take it years ago, but as lyme disease became more prevalant here, i started using deet and the vitamin b1 does make your sweat smell weird, so i stopped taking it

Wise Old Owl
02-22-2013, 22:14
FB Golden Bear NAILED it! if I have to go each each year and listen to experts in the field at University of Delaware... I could not post a better rant than he did! He did the research and did a terrific job!

Wise Old Owl
02-22-2013, 22:16
Deet works pretty good for me but my kids are allergic to it so we usually use Eucalyptus it works just as good.

Sorry waste of time... just a few words.... West Nile Virus. Now what is your plan?

WingedMonkey
02-22-2013, 22:36
Sorry waste of time... just a few words.... West Nile Virus. Now what is your plan?

I'm a DEET user myself, however for those that want to try other methods, the CDC says:


Oil of lemon eucalyptus [active ingredient: p-menthane 3,8-diol (PMD)], a plant- based repellent, is also registered with EPA. In two recent scientific publications, when oil of lemon eucalyptus was tested against mosquitoes found in the US it provided protection similar to repellents with low concentrations of DEET.

http://www.cdc.gov/ncidod/dvbid/westnile/qa/insect_repellent.htm

Pingus
02-22-2013, 23:03
Sorry waste of time... just a few words.... West Nile Virus. Now what is your plan?

Wow. I can think of way nicer ways to say that. :)

Wise Old Owl
02-22-2013, 23:08
Wise Old Owl

Since your so smart what do you suggest for people that are allergic to deet.

Spray the clothing instead!

Here is basic info for using this product on children.

DEET is absorbed through the skin, so it is important to use as low a concentration as is effective (10% or less for children) and as small an amount as is necessary. Up to a certain point, protection against insects increases with higher DEET concentration, but even low concentrations will protect against most bites. Some people experience irritation or an allergic reaction to DEET-containing products. DEET is toxic and potentially fatal if swallowed, so care should be taken to avoid applying repellent to hands or face or anything a child might put in the mouth. DEET should not be applied to areas with cuts or sores or around the eyes, since permanent eye damage can result from contact. High doses or long-term exposure to DEET have been associated with neurological damage. DEET can damage some plastics and synthetic fabrics, such as nylon and acetate, so be careful not to damage clothing or camping equipment.
How DEET Works

Biting insects use chemical, visual, and thermal cues to locate hosts. DEET is believed to work by blocking the chemical receptors for carbon dioxide and lactic acid, two of the substances released by our bodies that serve as attractants. Although DEET helps keep insects from locating people, there is probably more involved in DEET's effectiveness, since mosquitoes won't bite DEET-treated skin. However, skin only a few centimeters away from DEET is susceptible to bites.

Recommendations for Using DEET
Despite its hazards, DEET remains one of the safest and most effective insect repellents available. Here are some tips for using DEET safely:
Reduce your need for repellent. Avoid behaviors that will attract biting insects (e.g., avoid strenuous exercise or eating lots of high sodium or potassium foods prior to going outdoors, which increase carbon dioxide release).
Avoid applying chemicals that attract biting insects (e.g., floral-scented perfumes, scented sunscreens, dryer-sheet-scented clothes).
Where possible, apply DEET-containing repellent to clothes rather than to skin.
Apply DEET in a well-ventilated area.
Avoid applying DEET to hands, the face, or any injured or sensitive skin.
Avoid behaviors that will lessen the duration of DEET effectiveness (e.g., perspiration, rain, mixing with sunscreens).
When you come indoors, wash off DEET-containing products using warm, soapy water.

rka001
02-22-2013, 23:09
I was going to buy some eucalyptus with the lemon oil and the gentleman at the outfitters told me not to because it would attract bears.

Wise Old Owl
02-22-2013, 23:14
Wow. I can think of way nicer ways to say that. :)

Oh why mince words... you are new, no biggie,,, we are all here to learn something...

starbright
02-23-2013, 01:25
Wise Old Owl

Since your so smart what do you suggest for people that are allergic to deet.

Wise Old Owl
02-23-2013, 09:33
Go get the kids allergy tested with the back scratch test. ( I had it at age ten and 18) Then start the shot program based on the test. after that most allergies will disappear, or be reduced.

The common thought is if you are allergic - avoid the thing that you are allergic to... I am allergic to cats. There for I avoid cats.... this thought process is flawed... Science is based in fact and would tell you go get a cat and live with it... about 3-5 months your immune system will adapt and the allergy will diminish.

Recently Doctors have been giving kids with allergies to Peanut Butter Patches with Peanut Butter ... like the Nicotine Patches...

If the kids are allergic to Milk they give the kids cookies with small amounts of milk in them...


Many products claim to reduce mosquito bites & tick bites. In severe area's Deep Woods Off is the clear winner.

Wise Old Owl
02-23-2013, 09:42
Patches ....


http://www.dailymail.co.uk/health/article-2185409/Skin-patch-free-thousands-sufferers-peanut-allergy.html

Milk

http://en.wikipedia.org/wiki/Milk_allergy

Cookies May Help Kids Beat Milk Allergy


http://www.medpagetoday.com/MeetingCoverage/AAAAI/25448


Starbright - I know I am not going to change your mind here, but understand my allergies to poison ivy was so severe, my mother got Doctor's advice and did something about it, to this day I am not allergic anymore.

Colter
02-23-2013, 09:50
My first guess is the experiment was set up in such a way that it doesn't reflect real-world conditions. I have successfully used DEET hundreds of times where the skeets were thick. It's worked well every time. If they are becoming resistant I'll believe it when I see it.