DEET vs. Bug-Off Informal Challenge

I had a chance to participate in an informal bake-off between DEET-based spray and Bug-Off treated clothes yesterday, and thought I would share the non-scientific results.

Testing Grounds: Old Waterville Road "Jughandle", off Route 49 in Waterville Valley. Last year at this time, we took a family walk to the old cemetery and discovered that, at least in mid-May, the trail is absolutely infested with brown dog ticks -- kicking through the grass over the first half-mile, I picked up half a dozen on my legs. We learned that regular "tick checks" were essential. That walk also inspired my wife and I to go on a minor online shopping spree, where we outfitted the family with Bug-Off clothing from ExOfficio (pants, shirts, socks and hats... dorky, yes, but we hates the bugs).

Subjects and Conditions: The Usual Suspects... five adults and five kids, out for a noon stroll. The conditions were nearly perfect -- temps in the low 60s, partial sun, dry trail. The subjects wore long pants (8 of 10), capris or shorts (2 of 10). Four subjects wore ExOfficio Bug-Off treated pants, socks, and long-sleeved tees. Six were not wearing Bug-Off, but were spritzed liberally about the shoes, ankles, and lower legs with DEET-based Off!. The Bug-Off subjects did add a supplement spritz of DEET around the shoes and ankles, too.

Results: Over the course of a 90-minute stroll, I flicked one tick off the outside of my dorky Bug-Off pants, and didn't have to remove any from the other three Bug-Off wearers. We were nearly continuously flicking ticks off the other subjects (numbering in the dozens) at routine tick-checks along the way. We did a thorough tick-check back at the cars (or so we thought), which resulting the flicking off several more brown ticks. 20 minutes later, I heard the surprisingly calm voice of one of my 7-year old passengers exclaim, "Yuck, there's a tick in my hair". I pulled into my friends' driveway and removed two more ticks from little Olivia's hair and shirt, then rallied another dad for "naked tick checks". Several more ticks were discovered under clothing, preparing to or starting to attach. None were found on Bug-Off wearers.

Final Score: OK, certainly not statistically significant, but over the course of the day, one tick founds its way onto a Bug-Off clad tramper. Virtually every other member of the crew had several latched on, and one girl who was wearing powder-blue pants must have had a dozen or more latched on at one point during the day. I am willing to say Bug-Off works pretty well in the field.

Thanks, Dave...

Excellent summary... I don't think I had ever specifically heard that permethrin was better for repelling ticks, but it sure seemed that way...

"There are pros and cons to using either DEET or Permethrin for personal use, but when it comes to efficacy of disabling ticks before they can feed on you: Permethrin wins hands down!...

...Once it is applied most ticks will curl up and fall off if they make contact with the clothing, and the ticks will eventually die if there is prolonged exposure."

That explains volumes. The little guys literally seemed not to be latching on.

Dave: nice link.

To a certain extent, this is a comparison of apples and oranges. The two treaments work by different mechanisms, only one of which is appropriate for ticks. (Of course, comparison of the final result is valid, even if the different methods use different mechanisms.)

* DEET is a repellent. (Actually is is not really a repellent, just a blinding agent--its vapor interferes with mosquitoes ability to smell and find humans. It does not necessarily chase them away.) There is no fundamental reason why it should work for other species. (It may or may not work on another species if it happens to use a similar mechanism for finding humans.)

* Permethrin is a contact insecticide. (A nerve poison, IIRC. It kills or disables insects upon contact.)

Ticks sit on plants and latch on to you when you brush by--they don't fly around and find you by smell. If you are wearing permethrin on your clothing and they touch it, they will be disabled or killed. Unless ticks happen to be annoyed or damaged by DEET there is no reason to expect it to repel them. In fact, the DEET treated subjects may have been completely unprotected from ticks. (Your experiment did not include an untreated control group so it did not address this issue.)


The best defense is a layered approach. Permethrin on your clothing and DEET on your skin. (I personally use permethrin on my clothing and only use DEET or picaridin on my skin if the mosquitoes are bad.)


BTW, Buzz-Off (tm) clothing is just permethrin treated clothing. You can apply permethrin on whatever clothing you already happen to have. Both soak-in and spray-on versions are available at hiking stores.

Doug

probably justa typo...but the line is called "Buzz Off" and their treated clothing will have a logo on it so as ot to get confused with their other untreated clothing...

The missing control group

DougPaul said:

(Your experiment did not include an untreated control group so it did not address this issue.)

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Well, it did include a control group, but I thought it would be best not to mention it, since the two small children who made up the control were in fact snatched from our midst by Ticks of Unusual Size. No reason to give the child welfare agencies any more data than absolutely necessary.

When we bought the ExOfficio and Mumz treated clothing, we did it mainly as a convenience, but I did note that there are several brands of spray-on treatments available and might go that way next time so I can get better fitting clothing in materials I prefer. I will also be curious if the treatment in the factory-applied clothing really lasts for 25 washings (which might be a whole season or more, if you don't mind a bit of eau de trail on the second day.

DrewKnight said:

Well, it did include a control group, but I thought it would be best not to mention it, since the two small children who made up the control were in fact snatched from our midst by Ticks of Unusual Size. No reason to give the child welfare agencies any more data than absolutely necessary.

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Slurp!

When we bought the ExOfficio and Mumz treated clothing, we did it mainly as a convenience, but I did note that there are several brands of spray-on treatments available and might go that way next time so I can get better fitting clothing in materials I prefer. I will also be curious if the treatment in the factory-applied clothing really lasts for 25 washings (which might be a whole season or more, if you don't mind a bit of eau de trail on the second day.

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Permethrin, once it has dried on the clothing, will survive washing. The description on the REI website claims that the apply-it-yourself products will last six weeks or six washings. http://www.rei.com/search?vcat=REI_SEARCH&query=permethrin&x=0&y=0

Doug

DougPaul said:

(Your experiment did not include an untreated control group so it did not address this issue.)

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And you should have rather large groups. I'm sure everyone around here knows how some people are bug magnets, while others are not. (I think it's that some people are so mean and nasty, that even bugs won't go near them, but that's another story.

Because of the fact that personal taste plays such a large part, a proper experiment would better be conducted by the same person, with different applications on their left and right sides. (I did this once, but unfortunately, probably due to my dyslexia, I forgot which half was which)

So, the next time you go out, split the group into thirds, and in each of those groups have people mixed with on of the three meaningful combinations.

-Pete (who has a thing about experimenting with half a body)

No one ever wants to be in the control group...

That's the problem with the placebo group... no one ever wants to be there, especially when you KNOW the other two groups are going to win.

I poked around a bit... if this is going to be a big tick season, then a big bottle of permethrin is probably in order. Amazon has a pretty good deal at $17 for a 24-oz. spray bottle, and REI is even better at $12 for the same bottle of Sawyer's.

As Dave's linked article suggested, you can get industrial drums of veterinary permethrin for a much lower cost per ounce, but my coat is already soft and shiny as it is, so I will probably stick with the preparations intended for human use.

DrewKnight said:

That's the problem with the placebo group... no one ever wants to be there, especially when you KNOW the other two groups are going to win.

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I have no problem being the one without any chemicals. I never use them.

I don't blame you, Carole

carole said:

I have no problem being the one without any chemicals. I never use them.

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DEET is nasty stuff, and permethrin comes with a MSDS attached, so it can't be all that good for you either. That said, what do you do instead? Natural repellents? Suffer with bites?

I will admit to having a life-long irrational aversion to ticks, and I am pretty sure that the whine of a mosquito in the dark is the sound Charles Manson heard just before he recruited his disciples... so I need something that works.

I am a bug magnet, often with or without any bug dope on. I rarely use anything at all, but I won't use anything with DEET. My choice is Old Woodsman Bug Dope. It helps with the insects, the only problem is that it consistently repels people. I am convinced that it's called Old Woodsman because they ground him up and put him in the bottle.

DrewKnight said:

what do you do instead? Natural repellents? Suffer with bites?

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Neither. My husband says I just out run them. Maybe. But I don't always move fast. I do regularly take B vitamins (which some say helps and some say is hogwash). I stopped using chemicals several years ago and rarely have a problem. If the bugs are heavy I just move on. I only occasionally get bit. And I check often for ticks but have little problem with them.

In my experience, mosquitoes and black flies like potassium (bananas) and dislike garlic.

Tim

Of course what ticks really love is the smell of butyric acid which is present in the sweat of all mammals. Even freshly showered ones.

Drew, reading your report gave me the willies.