permethrin sleep sack

[peter t]

Does it stand to reason that climbing into something like a S2S sleeping liner with Insect Shield – in the nude – would go a long way to killing any teen ticks I may have missed / could not detect? Lyme season off to banner year here in the North East USA…

[Bob K]

Sounds reasonable to me. I found some research into using p<span class=”highlight”>ermethrin</span>-treated sheets for malaria prevention. No mention of the test subjects sleeping in the nude, however.

[BlackHatGuy]

Interesting question. A bit of googling doesn’t really answer the question. Most places say a tick crawling across permethrin-treated clothing will die quickly. One site said on contact. But ticks have hard backs, so by contact do they mean ‘feet’ contact (sorry, can’t think of the proper word, so you’ll just have to imagine ticks with feet…. :-) or any contact? And does it matter if the tick is simply crawling on you, or is embedded?

I’d pose the question to your local Dept. of Agriculture tick guru, or perhaps any local infectious disease specialist.

[Kenneth Keating]

It would kill ticks as long as they’re in contact with the liner.

[peter t]

Thanks all for the replies. Having searched around the web what I remain unclear about is just how much contact is required for the permethrin material to do its job. For example, if very little (both in the sense of time and amount ) then it seems a light once over with an Insect Shield camp towel at the end of a hiking day before sleep would be a simple & quick solution. Anyway, I’ve ordered the sleep sack for some extra peace of mind.

[Kenneth Keating]

The central coast area here in Calif is full of ticks and poison oak.  When hiking in this area I spray the inside and outside of my shirts and pants with permethrin, two sets worth.  One set is for hiking.  The other is for sleeping.  I don’t bring two sets of clothes when hiking in the sierra, but because of the large amount of poison oak along the coast I don’t want to risk getting poison oak transferred from my cloths onto my quilt.  This may be another option for you as clothes offer a closer fit, much more so than a liner.

Someone at my work became infected with Lyme disease via a tick.  Unfortunately he did not obtain treatment until too late.  It took him years to recover, and it was painful.  He’s still not fully recover.   After seeing what he went through, I’m extremely careful, I  want to avoid at all costs getting bit by a tick.

 

[James Marco]

Well, I am not a specialist. I do know a little about permethrin, though, having used it for 20 years or so and studying it intensively before that. I have degrees in chemistry, and biology and most recently computer/information science/logic. Anyway, permethrin is a nerve poison rather specific to insects. Some mammals are effected (cats) some are not (dogs, pigs, humans.) It extends in toxisity to fish/amphibians.

The strength of the reaction depends on the strength of the exposure and the type of organism. Say for a tick, normal permethrin treated clothing will kill it in 1 to 24 hours. This varies with concentration left in the cloths, water & water vapor, temperature, time of exposure, resistance of the organism, and a few more things I likely forgot. Sounds bad, but, the tick will loose interest in feeding in a few minutes. As soon as he is exposed and his brain can register the accelerated neural impulses, he basically looses interest in feeding to do “other” things. I think of this like a “meth head” looses his appetite and can go for days without food though this is an analogy only.

A deer tick reacts fairly quickly to newly treated clothing and will usually die within a couple hours. In the mean time, he will not feed, hence infecting you with lyme disease. Larger ticks can also carry Rocky Mountan Spotted Fever. They take a bit longer to kill, but have essentially the same reaction. There are several other diseases of lesser concern.

Note that wet clothing will cause a tic to be more heavily dosed. Dried permethrin is not toxic until it has entered the insects system. Water mixing with permethrin is far more lethal than him landing on your dry clothing and buzzing off again. Blackflies will often land on my sweaty shirt and crawl around a bit. They then buzz off and follow me in a cloud but have lost interest in biting. They just buzz around landing and taking off repeatedly.

Permethrin is NOT a repellant, though. The insect, think mosquito, must land on you. He has a window of something less than a minute, soo, a mosquito can still bite you. It is NOT effective against malaria because of this. Ticks and blackflies are much slower to bite. So, they can be “repelled”, though this is not really what happens.

Like I say, there is really too much going on to say how much for how long. It varies from bug to bug. They do not excrete it, so, I think it is always fatal except in minute doses. They are too nervous and jerky to feed properly. So, they can live for quite some time even without feeding. Constant exposure, like being trapped between your skin and your cloths, will kill them within 24 hours. Quicker if your cloths are wet from perspiration.

[peter t]

James, brilliant: thanks so much for taking the time to share this excellent information.

[Greg Mihalik]

“Having searched around the web what I remain unclear about is just how much contact is required for the permethrin material to do its job.”

 

From  https://www.ghdonline.org/uploads/ADA511583.pdf –

Ticks were placed on the industry treated fabric and monitored until “knockdown” (immobility)

“Hard ticks were most susceptible to the new polymer-coating method, resulting in prelaundering 100% knockdown times of 7.0 +/-0.9 min, whereas equivalent times for the dipping methods were 7.9 +/-0.35 min and 8.0 +/-0.54 min, respectively.

“After 100 launderings, 100% knockdown of I. ricinus nymphs was reached at 15.2 +/-1.04 min using the polymer-coating method, compared with 178.8 +/-24.7 min and 231 +/-53.6 min, respectively, using the dipping methods.”

 

 

 

 

[peter t]

Thanks… but did this really make the answers to my question perfectly clear to you? What I read is that if you take a tick thats cold and thereby moving very very slowly, enclose it in a tube lined with permethrin treated cloth that hasn’t been laundered yet, and after ~ 7 minutes they’re dead.

I am still left wondering about what a test somewhat closer to real world conditions might reveal… say a briefer exposure, maybe for a few seconds or even a minute as the tick walks up a sock or brushes past  the inside hem of my treated boxers as it works its way up the leg? Will they still die but just more slowly? Does any contact – of any length of time –  result in them going all wobbly and not biting. I still don’t know.

[Greg Mihalik]

“In a new study, published today (May 24) in the Journal of Medical Entomology, researchers showed that permethrin-treated clothes can seriously mess up a tick’s stride. Stick some adult ticks on a pair of regular pants tilted at a 45-degree angle, and 100 percent of them will still be clinging on 5 minutes later. Stick adult ticks on a pair of tilted pants treated with permethrin, though, and 42.5 percent will tumble off entirely. Even those that remain get seriously messed up. The researchers found that only 25 percent of the ticks were moving normally even 24 hours after exposure.”

https://www.livescience.com/62652-anti-tick-permethrin-coating.html

 

“A comparison of the impact of a permethrin-treated textile across tick species and life stages revealed the strongest effect on I. scapularis nymphs (0% with normal movement 1 h after a 1-min exposure), followed by A. americanum nymphs (14.0%), I. scapularis females (38.0%), D. variabilis females (82.0%), and A. americanum females (98.0%). Loss of normal movement for all ticks 1 h after contact with the permethrin-treated textile required exposures of 1 min for I. scapularis nymphs, 2 min for A. americanum nymphs, and 5 min for female I. scapularis, D. variabilis, and A. americanum ticks.”

https://academic.oup.com/jme/advance-article/doi/10.1093/jme/tjy062/4999656

 

“Our results indicate that permethrin-treated textiles provide minimal non-contact spatial repellency but strong contact irritancy against ticks, manifesting as a “hot-foot” effect and resulting in ticks actively dislodging from contact with vertically oriented treated textile.”

https://www.sciencedirect.com/science/article/pii/S1877959X17302108

[James Marco]

Exactly. Contact time will effect longevity of the insect. But, this remains relatively unimportant, since we expect some sort of lethal dose to be administered with modern technology. But, this is entirely statistical based, and based on the insect. Such experimental results do not really apply to a real life situation in the woods.

Again, the interest is in the *feeding* behavior of the insect in question. Even at relatively low doses of permethrin, we see a lethal dose administered, even if it takes a somewhat longer time to kill it. The big BUT, is the feeding behavior of the insect. Yes, permethrin interferes with normal feeding behavior. And, it happens much faster and at a lower dose than when an LD100 (lethal dose for 100% of individuals) is administered.

The studies above do NOT track this. Since LD100 is “assumed” to be rather well known, this IS something they can track easily, even though incorrectly. An LD50 (lethal dose for 50% of individuals) still leaves 50% of individuals ready to feed on you. This does not track with 100% lethality. The feeding behavior of the insect (or bug) may or may not be effected by an LD100. WHAT? Yup, he may already be dead but will still bite you before he lays down. I am sure you have heard of this with some flea sprays and dogs…

Anyway, I stand by my previous statements. In general, low doses and feeding behavior have not been well studied, I’ve looked… Soo, all you got is anecdotal evidence. Take it or leave it. It ain’t my ass that gets bit.

[Rex Sanders]

At least two reasonably well-done studies show that permethrin-treated clothing stops a lot of tick bites:

https://backpackinglight.com/forums/topic/91472/

The ticks could have died, lost interest, fallen off in a haze of chemical-induced stupor, or something else. Doesn’t matter – tick bite numbers were way down, and that’s what counts.

I treat my hiking clothing (shoes, socks, shorts, shirt, hat) [almost] every year with Sawyer Permethrin Spray. I hike in prime tick country frequently, and it seems to work. For a sleep sack, YMMV.

— Rex

PS: This year I forgot to treat – and got a tick bite. Sigh.

[Dean F.]

I have used permethrin a lot in the military, in some damned hostile places with bugs that will eat your face off.  (Sort of- leishmaniasis.)  The list of arthropod-spread diseases in places I’ve been is terrifying: in addition to leishmaniasis there is malaria, typhus, plague, filariasis, Yellow Fever, Dengue, etc.  African Sleeping Sickness (aka trypanosomiasis) , for the Love of God!  And then of course all of the Rickettsial stuff here in North America.  I stopped using DEET a decade ago because that stuff scares me.  No doubt it works very well, but it scares me, and the eating plastic thing can be annoying.

Anyway, the military went to permethrin clothing treatments in a big way and it clearly works extremely well.  This is just anecdote but I have never had an insect-borne disease, or even been bitten badly enough that I remember it today, so I’m continuing with permethrin.  I do use a mesh head net in high pressure areas, though.  (Also treated with permethrin.)

But I’m a physician, and as a military physician I have great motivation to engage in force health protection and preventive medicine, so I’m very diligent with my permethrin-treated clothes.  Others may have differing experiences.

[Valerie E]

Since permethrin is so central to this discussion, let me re-post from another thread (hopefully this will help some folks:

When does Sawyer Permethrin Spray become un-usable?

>John Smith <[email protected]></div>
Sun 5/27/2018, 5:07 PM</div>

The permethrin lasts about 10 years. Look at the color after shaking well, if it’s white its good – brown to black it’s bad.  You need 4 oz on an outfit or it’s not going to be effective.

[Author]

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