Repelling Insects

This item appears on page 43 of the August 2008 issue.

Harry Pearson of Cape Canaveral, Florida, wrote, “A reader suggested using Avon Skin So Soft bath oil mixed half and half with rubbing alcohol as a mosquito repellent (March ’08, pg. 4). Avon claims this product to be both a sunblock and an insect repellent. I believe it has limited use as a sunblock and is worthless against mosquitoes.

“A heavy application will protect against no-see-ums, properly classified as biting midges, but, rather than the biting midges’ actually being repelled, I believe this protection is physical. They are so small that they find the layer of oil difficult to bite through. Therefore, diluting the bath oil with alcohol would reduce the effectiveness.

“A few colleagues of mine who spend time in the tropics claim DEET protects against biting midges, but they always speak of ‘heavy application,’ which suggests they also are providing the necessary layer of oil on their skin.

“DEET is the recommended repellent against mosquitoes and some other insects of near equal size.

“I would be interested in reading what other ITN readers use as protection against insect bites, particularly in areas where malaria and other mosquito-borne diseases are present.”

So we asked readers, “What works for you? What doesn’t?” Following are responses received. If you have anything to add, write to Repelling Insects, c/o ITN, 2116 28th St., Sacramento, CA 95818, or e-mail editor@intltravelnews.com (include the address at which you receive ITN).

Living in Minnesota and traveling to various countries with mosquitoes and other biting insects, I’ve found that only DEET works. (The exception was Australia, which, like its football [soccer] rules, apparently is an exception for mosquitoes as well, as only a local concoction worked for me.)

I tried Avon Skin So Soft and it was useless.

One caveat — DEET may not be safe for young children. Check with the CDC or your doctor.

Kent Shamblin

Beaver Bay, MN

I’ve had good luck with Avon Skin So Soft bath oil when working in my yard, attending outdoor parties, etc. I don’t dilute it with anything, and I make sure it covers any exposed skin on my arms, legs and feet.

It seems to work on both mosquitoes and no-see-ums; however, I live in the desert and we typically don’t have swarms of mosquitoes, even during the summer rainy season. Our mosquitoes can carry West Nile Virus but nothing more serious.

When traveling to areas where malaria is present or when taking all-day hikes in areas where swarms of mosquitoes are common (increasing the chances of getting bitten), I go straight for a repellent containing DEET and spray it on my clothes as well as on my skin. The risk of contracting a life-threatening disease outweighs the risk of using the chemical for a couple of weeks, in my opinion.

Bill Kizorek on a gorilla trek near Bukavu, Democratic Republic of Congo. Photo: Two Parrot Productions

Bonny Brady

Tucson, AZ

We take groups to many mosquito-infested areas, from the Amazon region to Africa. We encourage a yellow fever inoculation and antimalarial pills such as Larium (stronger side effects but very effective) or daily Malarone. Personally, I prefer doxycyclene, yet U.S. physicians seem to feel it’s not effective.

Any prophylaxis will considerably reduce your chance of contracting malaria if bitten by an infected mosquito, if you complete the entire course of prescribed meds. My local guides often state that nothing is 100% effective against the four different strains of malaria, however early diagnosis and treatment will usually result in a cure.

After dusk, we suggest wearing light long pants and long sleeves along with a topical repellent containing 30%-35% DEET. There are hundreds of new such products now on the market from which to choose.

Many feel that the higher the percentage of DEET, the safer they are. One client on safari brought a repellent so strong, it ate through her canvas bag. Imagine such contact with skin! Others applied repellent so strong that it ruined their clothing and sunglasses lenses.

I never use Skin So Soft, as it seemed that the fragrance actually drew more bugs to me. Never wear perfume.

Good websites are the World Health Organization’s www.medicine planet.com and Britain’s National Travel Health Network & Centre’s www.nathnac.org.

Suzy Davis, Adventures For Singles, Smyrna, GA

I use Avon Skin So Soft in my bath all the time and the mosquitoes still love me.

For repellent, Muskol (www. muskol.com) can’t be beat. You can get Muskol with various strengths of DEET (N, N-diethyl-m-toluamide), from 25% up, depending on if it is a spray, liquid or lotion. Up in Alaska we used to get the liquid at 95%, but that is dangerous for kids’ brains and can melt the rubber on lawnmower handles.

Other commercial repellents often have 5%-10% DEET, which does not work very well. Anything over 20% DEET should work okay for mosquitoes, deer flies and ticks and, if you follow the directions, still not fry your brain or melt your socks.

Kit Stewart

Sequim, WA

A check of my travel records tells me that since October 1996 I have traveled to seven areas which required or highly recommended using antimalarial medications.

When I visited with the travel nurse at Kaiser to obtain a prescription for the medications and any other vaccinations I might need, I was always given literature from the U.S. Department of Health & Human Services detailing what precautions I should take for the area I was traveling into. All the literature spoke to the need for using DEET to repel insects and mosquitoes.

A few years ago there was mention of perhaps using permethrin spray on all of one’s clothing. I used it for the first time when I went to Papua New Guinea and subsequently when I traveled to Costa Rica and several countries in South Africa.

I know that many people balk at putting 100% DEET on their skin; however, I can attest to the fact that while using it I did not receive any mosquito bites.

An added bonus of using the permethrin on your clothes is that you don’t have to use very much of the DEET for it to be effective. I use it sparingly on my neck, wrists and ankles, with a little on my forehead.

These precautions have worked very well for me. I purchase my DEET and permethrin at REI (800/426-4840, www.rei.com).

Josephine Guilino

Sacramento, CA

On a trip through the Copper Canyon in Mexico in fall 2007, I took Bounce dryer sheets and kept one in my pocket when we were in areas with mosquitoes. I did not get any bites.

Our guide said there were fleas in the place in Batopilas where he slept, so he used one and did not get bitten.

I will certainly try it again, as I hate to use DEET.

Susan Haggard

Los Alamitos, CA

Excellent topical repellents can be purchased at REI, Sportsman’s Warehouse (based in Midvale, UT; 801/566-6681, www. sportsmanswarehouse.com) or other outdoor camping retailers, including the mail-order firm Campmor (400 Corporate Dr., Mahwah, NJ 07430; 800/525-4784, www.campmor.com).

These products include the 12-hour Ultrathon and REI Jungle Juice (both with DEET). We also sprayed our clothes with pyrethrim before packing.

Vitamin B-1 (200-300mg) taken orally each day of exposure offers excellent protection, as it is excreted through the skin and insects don’t like it.

Also, remember to contact your doctor and/or the local, county or state health department for a yellow fever shot and an antimalarial prophylaxis.

My husband, John, and I have visited the Upper Amazon Basin (May ’03), Guayaquil, Ecuador (May ’05), and Guadalcanal in the Solomon Islands (January ’08) and never sustained a bite.

Mary Jean Davison

Sandy, UT

I have not only taken many trips to hot, humid climates (including several to the Amazon), I live in the hot, humid southern Appalachians. I have had good luck with the following.

First I rid myself of as many fragrances as possible. My clothes are washed in a nonperfumed detergent (I use all® Free Clear), I rinse my hair thoroughly after bathing, I do not use hairsprays, and I use an unscented deodorant. This alone does a good job of repelling my local bugs.

When they still have been bad, as during a camping trip or a tropical vacation, I have had good luck using 3M-brand Ultrathon, which is 33% DEET in a time-released polymer. DEET in percentages over this amount has proven to be no more effective, and the time release lets the effect last for much longer. If you are in tick country, be sure to use it around your ankles.

Also, before I leave I thoroughly spray my outer clothing with per­methrin. This should not be sprayed on garments close to the skin, so I spray both the hat I wear for sun protection and a lightweight, loosely fitting, long-sleeved shirt that I can wear over my other clothing. Permethrin in a spray can be purchased at various outdoor-supply stores, including the camping section of Wal-Mart.

Many, many years ago I heard that large doses of vitamin B-1 provided an effective mosquito repellent. I did not know what a large dose would be, but my doctor said it couldn’t hurt, so, starting several days before I left on a 2-week trip to the Upper Amazon, I took 1,000 milligrams three times a day for a daily total of 3,000mg.

We were sleeping under netting in an open-air lodge, and while others in our group could hear mosquitoes buzzing all night, my roommate and I didn’t even hear any.

I do not recommend B-1 for long-term usage, nor do I know if this would help repel other insects.

Margaret F. Olson

Pleasant Hill, TN

Even with the humidity in Bukavu, Democratic Republic of Congo, ExOfficio’s Insect Shield garments dried in three hours. Photo: Two Parrot Productions

For repelling insects, my husband highly recommends what he used on a 3-week birding trip to Peru in September ’06: Permethrin Clothing Insect Repellent from Sawyer Products (Safety Harbor, FL; 800/356-7811, ext. 10, www.sawyer.com) 800/356-7811, ext. 10). One outfitter that carries this is Cabela’s (800/237-4444, www.cabelas.com).

Following the directions on the can, he “wet” his clothes with the spray three times; some people just spot-sprayed and were not happy campers.

He wore a sun-protective long-sleeve shirt along with jeans, boots and a hat. An entomologist saw him at one point and reminded him to roll down his sleeves and tuck his pants into his socks.

On his exposed skin (face and hands) he has used 100% Deet but has been happiest using OFF! Deep Woods (phone, from U.S., 800/494-4855 or, from Canada, 877/506-7352, www.offprotects.com/insect-bites).

The oxbows on the Manu River are about as bad as it gets. He said that in Amazonia the bugs have bugs.

Jean Byers

Burbank, CA

When we were in Belize a few years ago, my wife was badly bitten by no-see-ums. Nothing seemed to stop them until I walked into Placencia and purchased a box of Zebra-brand anti-mosquito coils (Kumar Enterprises, based near Mumbai, India; www.kumarentp.com).

I lit one of these incense coils each night and she had no more problems. One coil lasted eight hours and was harmless to her personally, unlike DEET may be.

We have not found the Zebra-brand coils in the U.S. but have bought a box of OFF! Mosquito Coils, which we carry when we travel and which we hope will be just as successful.

Homer A. Brown

Norman, OK

My husband, Clyde, and I often travel in areas of malaria and dengue fever. We always take prescription Malarone as a prophylaxis against malaria. In addition, we have used several techniques for keeping mosquitoes at bay.

Ten years ago our travel clinic doctor recommended spraying our clothes with permethrin prior to travel as a defense against mosquitoes.

Sawyer Products (800/356-7811, ext. 10) used to carry a 13.3% permethrin solution. At the time, the owner of Sawyer told me this could be diluted to a “military-strength” solution of 0.8%, eight ounces of which was supposed to last for 25 washings (if you were able to get all of it to soak into your garments when sprayed).

Sawyer now carries only the permethrin diluted to 0.5%, which they describe as military strength and say will last for six weeks (six washings) when sprayed at the rate of 4½ ounces for one outfit (a long-sleeve shirt and long pants).

Clyde and I saw this antimalaria mural on a narrow backstreet on Gulangyu Island, Fujian, China, in March 2003. Photo: Jane Holt

Since we travel for months at a time and I wash socks and shirts nightly (not once a week), this was less than satisfactory. In addition, I always had trouble spraying our clothing with the permethrin. We wear primarily nylon (“performance”) fabric to very hot and humid climates and I could never be certain that the permethrin had permeated the fabric.

After visiting some websites that discussed the health factors of using permethrin on clothing, particularly the website www.safe2use.com/poisons-pesticides/pesticides/permethrin/cox-report/cox..., I became troubled by the risks. We no longer use permethrin.

In addition to spraying our clothing, we used to use and still use a Sawyer lotion to protect exposed skin. Sawyer’s controlled-release 20% DEET lotion, which encapsulates the DEET so it does not permeate the skin (or so they say), is the best product we have found.

We do not use combination sunscreen and insect repellent since I have read that, in combination, neither component is as effective as using each separately. (For sunscreen we use Bullfrog Quik Gel Sport Spray.)

In India, when we are in hotels without tight window closures, at night we plug in our Good Knight Turbo Liquidator machine, made by Sara Lee (www.godrejsaralee.com). This is a small gadget similar to plug-in room air fresheners familiar in the U.S.

Screw a small bottle with liquid mosquito repellent into the bottom of the device, plug it into any outlet (a little light comes on to show that it’s working) and the liquidator takes up the repellent through a wick and vaporizes it. In 30 to 45 minutes the Good Knight will knock out all the mosquitoes in an average-size hotel room.

It works well to plug it in just as you’re leaving for dinner so that the room will be mosquito-free by the time you return. It’s a very effective device, and in India probably every household with electricity uses some form of it in every bedroom.

Hotels often provide one for each of their rooms. If we find one there, we use our unit in the bathroom. This is especially important, as hotels of all classes often have permanently open windows or vents in the bathrooms, and frequently there are damaged screens or no screens at all.

We bought our Good Knight device with a 45-day bottle of liquid two years ago for 60 rupees (about $1.50 at today’s exchange rate). Refill bottles come in 15- to 90-day sizes and cost very little. There are several competing brands (such as All Out and Hit) which work just the same. We’ve always found the refill bottles to be interchangeable between brands.

It’s easy to find any of these, sort of. Both the device and the refills are sold at different types of stores in different states. We bought our Good Knight starter kit at a chemist’s in Maharashtra, but when we asked for refills at a chemist’s in Orissa, we were sent to a stationery store. In Mumbai we got a refill in a grocery store. In Delhi we got one from a street vendor.

There is another version of mosquito-killing machine. It uses a dry tablet, or “mat,” about the size of a postage stamp. The mat is slipped into a slot in a little machine which plugs in just like the vaporizers. The machine heats up and slowly melts the mat, releasing the mosquito repellent.

It has the advantage of using a dry product, but it has the extreme disadvantage of getting very, very hot. It’s not the sort of thing that can be unplugged and packed in a hurry. The liquid version can be packed after only a short cool-down period.

The dry version has another disadvantage: it’s designed to use up a mat in about eight hours; if you forget to replenish it at night, you’re out of luck. The liquid version keeps cranking out the repellent until it’s unplugged, it has a large supply, and you can see through the clear bottle how much is left.

We find the Good Knight such a reassuring presence in mosquito country that we always get refills before leaving India so we can carry the Good Knight to other countries where there are dangerous mosquitoes.

In case we find ourselves someplace without electricity, we also carry a few mosquito coils, just like the ones you use at your backyard barbecue (and bought from the same sorts of places that sell the Good Knight).

Finally, we always appreciate it when our room has a resident gecko who feasts on mosquitoes while we sleep.

Jane B. Holt

Hinesburg, VT

On my last trip to Africa, visiting an area just outside the town of Bukava in the Democratic Republic of Congo in May ’07, we took a 5-hour trek up a jungle mountainside to film a magnificent silverback gorilla family.

Along the muddy path, gigantic voracious fire ants attacked our party of six. Dressed in shirt, pants, socks and hat of ExOfficio’s Insect Shield (formerly Buzz Off) bug-repellent line of clothing, I was the only one of us who escaped the wrath of those little red monster jaws.

It was apparent that those ants did not like the permethrin that was part of my clothing fibers. Permethrin is a man-made version of a natural insect repellent found in certain chrysanthemum plants.

Insect Shield (www.insectshield. com), a company that works with ExOfficio, binds a proprietary permethrin formula tightly to fabric fibers, resulting in effective, odorless insect protection that lasts beyond the expected lifetime of the apparel.

The repellent gear has been proven and registered to repel mosquitoes, ticks, fleas and flies. I have washed one shirt 40 times and it still works perfectly, and Insect Shield’s tests show effectiveness after 70 washings. (Just don’t send it to the dry cleaner!)

I bought my clothes online at the ExOfficio site www.exofficio.com. They are listed under the Insect Shield section under the men’s and women’s drop-down menus. The clothing is also available at some outdoor recreation supply stores such as REI.

I bought the Baja Long-Sleeve shirt for $85, the Convertibile Pant for $80 and a variety of the socks for $10 to $20 each. I also bought one of their baseball hats.

On my last three trips to Africa, I wore the garments every day, all day long, and never did a bug land on me. Each time, by the way, I was in malaria territory.

A bonus to wearing this stuff is that it does not smell, it is not sticky, it looks great, it “breathes” well, and the lightweight clothing feels soft on the skin. At night I would wash the pants and clothes in the bathtub, and three hours later they would be dry!

Bill Kizorek

Lisle, IL

In protecting against mosquito-borne diseases, the Centers for Disease Control & Prevention (CDC) recommends the use of products containing active ingredients which have been registered by the U.S. Environmental Protection Agency (EPA).

For use as repellents applied to skin and clothing, the following are EPA-approved products, indicating they have been approved when applied according to the instructions on the label: DEET (from 4% to 100%) and Picaridin, both of which are “conventional repellents,” and oil of lemon eucalyptus (or PMD) and IR3535, both of which are “biopesticide repellents,” derived from natural materials.

Certain products containing permethrin also are registered with the EPA and are recommended for use on clothing, shoes, bed nets and camping gear.

Visit www.epa.gov/pesticides/health/mosquitoes/ai_insectrp.htm.