DEET
 

Have been reading up and did a search here too.
I understand that the only mosquito repellent recommended as 100% effective is DEET. But...no where do I see what percentage of DEET is the best.

Can anyone help?

Also on another thread that came up in the search someone mentioned that Picaridin (oil of lemon eucalyptus) is as effective as DEET.
Any more info on that?

Thanks!

The most effective are the ones that are close to 100% DEET (many of them will have about 95%). But, they also tend to be a bit smelly and unpleasant. I found a cream repellent on magellans.com that was designed by the US army and seems to work really well. As far as other things to use, to the best of my knowledge when people like Consumer Reports have tested them, the only one that really proves effective is DEET. Here is the link for the cream repellent:
http://www.magellans.com/store/Healt...ionSC115?Args=

The Ultrathon cream repellent mentioned above is available also at Walmart. I got mine there about a year ago.

At 100% you'll smell like a chemical plant. Generally, repellents should have at minimum 30-35% Deet, which works for most people. Deet does nothing for Tsetse flies... they just bit and they hurt. Mossies will stay away with even a small amount of Deet. Except for our time on hot and humid Zanzibar, we've never been bothered by mossies on safari. Whatever, you choose, however, do not put it on your face, near your eyes and be sure to wash off before going to bed. Sleep under mossie nets, if provided. If not provided, the rooms (in lodges) are pretty secure; you can always choose to spray the room before going to dinner. But, please don't overdo the spraying as it'll wind up on all surfaces, including your bedding.

Sawyer Co. makes an insect repellent called "Broad Spectrum" that is about 24% DEET and also has R-326, which they say is a special fly repellent. I used their earlier version of this product in Zambia and had no Tsetse fly bites, even though fellow travelers did.

I always use 50% strength DEET repellent and even at that strength I can FEEL the chemical strength of it - it's STRONG stuff. And the instructions not to spray/ apply it to plastic or various other materials (because it will do bad things to them) kind of makes me wonder what it does to my skin.

But having had a severe reaction to a mosquito bite as a kid (which had to be operated on - I still have the scar) I'm kind of keen not to get bitten.

That said, I was in India recently and spent one night in this former palace that had recently been converted to a hotel. The place seemed to be a global mosquito HQ - there were millions of the little beasts. They didn't have AC or mosquito nets for the beds. Even with an incredibly strong fan blowing gale force next to my bed and DEET all over I got 30-40 bites that night, most on my face, hands and feet.

Uuugh!

I don't think there is ANY repellent (even DEET at 100%) that is 100% effective.

Citronella is another more natural repellent - it smells gorgeous too. I wouldn't use it on it's own but perhaps combine it with the DEET.

If you have a small portable room burner you could take a pack of tea lights and some citronella oil and burn it in your room at night?

Thanks for all of the input.

What I get from this - and please correct me if I am wrong - that anything up to about 35% DEET is best?

I'd say upwards OF 35% (not under it) and up to 50%.

Look for 35% to 50% strength.

And if you can buy from a store that lets you try some on your skin before you buy - some people react quite badly to it as it's a strong chemical.

Thanks Kavey for the correction. Now at last I know what to buy!

You're welcome! Next question? :D

I read on multiple webpages, and have got the same facts from different doctors: "30% DEET is enough. There is no proof that products with more than 30% of DEET repel insects any better than a product with 30%."

Geez whiz pixel as if I wasn't confused enough!! Can I settle for 35% as a mean average? :))

Africanow - you certainly can - but my advice would be to try and test a 50% strength one on your skin - if you don't have any adverse reaction to it you may as well go for the 50% incase it does indeed give a slightly better protection.

These things are hard to measure, to be honest.

Main thing to remember - whatever strength you go for will NOT completely protect you from bites so make sure you cover up as much as possible, perhaps also use citronella or anti-insect coils in the room if there are a lot of mosquitos present, a mosquito net too (again only if there seem to be mossies present in the room) and make sure you take your anti-malarial medication religiously.

Thanks again Kavey. I'm going on a camping safari, not staying in lodges so it is important.

Long sleeves, pants yes. Citronella in addition to the DEET is a sound idea - at least on me and my clothing.

I am assured that the tents which are provided by the safari are mosquito proof with fine nets on doors and windows. I may add the citronella anti-insect coils too, just to feel safer.

Yes, got my prescription for Melarone today :)

All of your advice, and that of all others is much appreciated. Thanks!

Africnow,

The point I'm trying to make is; a lot of stores promote products with more than 30% DEET as being more effective. And you can guess it; these products cost more of course.

But there's no need to spend more money. The repellent does not become more effective once you go higher than about 30%. The only thing you really get is a downside; the smell.

Pixelpower, do you know of anywhere I can find more information on this as I'd be happy to use lower strength DEET if I could be confident it would work as well - as I said it's a strong chemical and I find it sometimes irritates my skin.

The only advice I've seen is that stronger than 50% shouldn't be used directly on the skin BUT that it can be applied directly to clothing. I've also read that stronger versions don't work better than weaker ones at the time of application (they work similarly well) but that they do last longer.

This is one of the articles I found on it - http://lancaster.unl.edu/enviro/pest...nsectRepel.htm - but I'd welcome more information.

I've also read that the most effective DEET repellent is 70% strength in ethanol - a repellent created for military use by the US Army. One of the messages I found on the net talking about this also said that 50% versions in ethanol with musk added were longer lasting than those without musk because musk, used in the perfume industry, makes the application persist on the skin for longer.

But I don't know how true any of these claims are and, unlike many medical areas, I can't seem to find results of any real comparison studies.

Any pointers appreciated...

LOL LOL Great article Kavey.

Repel the mosquitoes and attract the lions, cheetahs servals, leopards, etc. :))

Quote:
Catnip. Researchers at Iowa State University have found that nepetalactone, an essential aromatic oil in catnip, is about ten times more effective at repelling mosquitoes than DEET — the compound used in most commercial insect repellents. A patent application for the use of catnip compounds as insect repellents was submitted last year by the Iowa State University Research Foundation. Don’t expect this to be commercially available anytime soon, as it has yet to be analyzed by the US-EPA or tested by human subjects.

Yeah I did wonder whether I should just douse myself in catnip and attract those big cats even more but to be honest... all I need to do to find the big cats is request a toilet stop - as soon as I need to find that special termite mound or bush out comes the big cat!!!

:D

Kavey,

I read the "no use in more than 30% DEET" line about everywhere on divers fora out there. Cannot point to examples though.

But the thing is; there's 6 safari-shooters in our party, and we all went to a different doctor (well except for me & my wife as we are a couple) for advice and the necessary shots.

...and we all got the same advice from all these doctors. Seems they all open a medical book, and know immediately are able to tell you all you need to know, including the DEET-info.

OK thanks for that - that's good to know.

I'd be happy to buy less pungent DEET next time as it's not exactly good for the skin!

I decided to search the medical literature for evidence on the efficacy of various insect repellents. Here is a sampling of the findings:

<b>Catnip:</b> Two 2005 articles from the Journal of Medical Entomology reported comparison of catnip to DEET. Both showed some effect in artificial tests, but only one actually looked at people getting bit. They wrote in the abstract: &quot;We conclude that catnip oil and nepetalactone isomers are significantly less effective than deet or SS220 in deterring the biting of Ae. aegypti.&quot;

<b>DEET %:</b> A 2005 practice recommendation which reviewed the literature reported that concentrations of DEET over 30% offer no increase in effectiveness, but they are effective for longer durations. The full text is located at www.jfponline.com/Pages.asp?AID=1931

<b>Citronella:</b> A 2003 paper looking at topical citronella found it prevented bites for only 2 to 20 minutes. For candles (and I assume burning oil), one study found they were slightly better than regular candles, which were slightly better than nothing at all. Another study from 2000 field tested various non-topical products against topical DEET in Illinois. They found DEET beat all of the non-topical products, but that mosquito coils and deet-impregnated wrist bands were better than control. Reading between the lines, the other non-topical items, including citronella candles, were no better than no treatment at all.

<b>Picaridin and PMD:</b> A nice review article of sunscreen and insect repellents in Current Opinion in Pediatrics (2004, pubmed ID 15273497) cited studies showing comparable effect between 19.2% picaridin and 35% DEET. PMD (p-methane-3, 8 diol), a derivative of eucalyptus oil, was mentioned as comparable to DEET at high concentrations based on a review of field tests in Ethiopia. A separate article from 2004 Journal of Medical Entomology (pubmed ID 15298309) compared four synthetic repellants to eight plant-derived ones. Repel, containing 26% PMD, lasted longer that Off w/ 15% DEET, which in turn lasted 50% longer than a repellent w/ 7% DEET. The only other natural product that lasted longer than 7% DEET was Bite Blocker (2% soybean oil), which lasted as long as the 15% DEET. Before you run out to get Bite Blocker, the same product was tested in a 2002 New England Journal of Medicine article and found much shorter duration of protection. As is so often the case with medical literature, contradictions abound!

If you are a real glutton for information, there was an excellent review in the Annals of Internal Medicine back in 1998 that cited 122 papers. Free full text access is available at www.annals.org/cgi/content/full/128/11/931

That article cited perhaps the ultimate mosquito prevention: &quot;In a field trial conducted in Alaska, persons wearing permethrin-treated uniforms and a polymer-based 35% DEET product had more than 99.9% protection (1 bite/h) over 8 hours, even under conditions of intense biting pressures; unprotected persons received an average of 1188 bites/h.&quot; Ex Officio's BUZZ-OFF contains permethrin plus a prorietary compound, so if you're really worried about bites you can invest in some of that clothing.

-Matt

Thanks Matt!
So if I'm happy to reapply regularly, 30% DEET is fine, but 50% might be better if I'm not going to reapply as regularly because it will last longer?

Hi Matt,

This is very much appreciated indeed. Had someone from the USA offer to buy the DEET for me and ship it to me here in Israel.

So shall I ask her to get 35% DEET? I can pick up Eucucalyptus oil here, also lemon oil. Do they need to be mixed with anything special? The candles and insect repellent rings aren't worth the cost and trouble, if I understand correctly?

Thanks!

As an xnurse I agree with Matt in that medicine is a very inexact science and thus lot's of findings will change or be contradicted.
That said, most of the mosquito solutions are put into other compounds that will further dilute them of their % of DEET. Also, most of these products will break down after sitting in your closet for years/many mos. on end or by being exposed to temp. changes - so replace prior to your trip.
We brought 30% and wore the treated shirts when there were a few mossies buzzing around and didn't get bit once. As Sandi said, unless your around wet areas you won't see too many mossies. So take your maleria pills (unlike some folks :) , cover up and go enjoy your trip.
Sherry

Kavey-

The thing I failed to mention about % DEET and duration of effect is that some lower % DEET products have extended release formulations. The 1998 article I linked discusses this in the section &quot;efficacy&quot; under the DEET heading of the Chemical Insect Repellent Section:

&quot;Extended-release formulations of DEET have made it possible to reduce the repellent concentration without sacrificing duration of action. When tested under laboratory and several different environmental and climatic field conditions, the 35% DEET polymer formulation by the 3M Corporation was as effective as 75% DEET in repelling mosquitoes [19, 47-50]. The polymer formulation provided up to 12 hours of more than 95% protection, depending on the environmental conditions and species of mosquito tested [46, 48, 49, 51].&quot;

I believe that the 3M formulation cited is basically the Ultrathon product mentioned above by jcasale and tigerpaw (although I think it has a 24% version in addition to the 33% version make sure you're getting the one you want).

Africnow-

I'm not sure whether or not it's worth having DEET products shipped to Israel. It probably depends on just how concerned you are and how much protection you feel is necessary.

Your original post mentioned Picaridin as a natural product, but my reading said it was a synthetic like DEET which is touted to have less skin irritation. <b>PMD</b> is derived from oil of lemon eucalyptus (Eucalyptus maculata citrodion), which I think is different from just eucalyptus.

I copied the wrong pubmed ID for that 2004 test of various agents. If you want to read the abstract, go to www.pubmed.com and enter 15311467 into the search field. They tested several mosquito species and the following products had average protection over 7 hours: Autan (10% KBR3023 = <b>picaridin</b>, Bite Blocker (2% soybean oil), Off! (15% DEET), and Repel (26% PMD).

Can you get a product w/ 20% picaridin? In the US all we have so far is Cutter Advanced which is only 7%, but stronger products are supposed to be available in Europe and Australia (eg Autan Repel Army 20). Otherwise, you may be able to do homemade PMD repellent if you have lemon eucalyptus oil. This paper dissolved it in coconut oil and tested it in Ethiopia (pubmed ID 12672146):
www3.interscience.wiley.com/cgi-bin/fulltext/104085667/PDFSTART

You could combine the best repellent locally available with treated clothing (either BUZZ-OFF or treated yourself w/ permethrin). I would think that would be enough but if you are still worried you could get the DEET shipped to you.

-Matt

Hi Matt,

Thanks for the details. I am not having it shipped for use here but for my trip this August to Kenya and Tanzania.

I will however check on whether 20% picaridin is available as you suggest.

Thanks!

August is winter in East Africa. Cold nights and mornings (the mosie biting time) = no mossies (or few). So, too if at higher altitude, the mossies don't fly this high.

During daytime, temps will be mild, in the 60s or low 70s. So unless protecting yourselves from possible Dengue mossies that bite during the day, I'm sure you'll be fine with the 30% Deet.

Thanks Matt!
We have enough of the 50% stuff left for at least one more trip but I'm making a note of all this for the next time I need to buy some more!

Hi,

This is what my safari organizer wrote in answer to my question about weather in mid-August: &quot;On Ngorongoro Crater Rim it may be 4 Celsius just before dawn and down in the Crater 30 Celsius at 2.30 pm - if the sun's out. So be prepared for that range&quot;.

So I do want to be prepared for the mosquitoes too.

What would the British Fodorites say is the best DEET/Picaridin preparation available, please?

Thanks again!

Africnow,

Only the female mosquitos bite (and spread Malaria). And they only come out at night. Read; you need to be in an area where it's warm AT NIGHT to become &quot;mosquito-meat&quot;. ;-)

Yes, pixel we will be... :(

I was working in my backyard yesterday and we have more mosqitoes than I've ever seen in Africa. And that includes the Delta in Bots.

I sprayed with Deep Woods Off that contains 25% Deet. About 3 hours after I applied it I felt a mosquito bite so I reapplied. After about another 2 hours I was worn out so I went inside. I ended up with 2 bites.

So that is my experience with 25% Deet. Also remember when using high Deet content sprays that it will ruin plastic, rubber, nail polish etc (watches, cameras, manicures, pedicures!).

Hello,

For those in the UK: PMD is the active ingredient in Mosi-Guard, which can be bought at Boots.

Cheers,
Julian