Summer is just around the corner in the Northern Hemisphere. Are you ready to protect your kids from tick bites?
In the United States at least, fears of Lyme Disease from tick bites have recently eclipsed warnings about mosquito-borne Zika. Local and national news outlets have been covering the Lyme threat for several months.
They’re right to warn us. As maps from the U.S. Centers for Disease Control and Prevention illustrate, ticks carrying Lyme disease – like the blacklegged tick in the video below – now live in many of the continental United States. Ticks carrying other diseases (such as the cayenne tick in the image at the top of this post, and the similar-looking Rocky Mountain tick) can be found in all 48 contiguous states. Moreover, 47 of those states had reported cases of Lyme disease by 2015. All this means that if you live in the U.S., you need to know how to prevent tick bites.
But it’s not just U.S. newscasters warning that last winter’s mild weather means a record summer for ticks. (Which is bad news for anyone wary of Lyme Disease, Rocky Mountain Spotted Fever, Powassan Virus, and other tick-borne infections.)
According to a report published nearly a decade ago, the bacteria that causes Lyme Disease now lives in ticks throughout Canada, Europe, and even parts of Africa and South America. News sources from Canada to the British Isles are cautioning audiences to be alert to the increased risk of tick bites. In other words, knowing how to prevent tick bites is critical regardless of where you live or travel.
So let’s assume you’re a parent who wants to protect your kids from tick bites. What do you do?
Enter my friend Renée. A few weeks ago she asked what we used for bug repellent. She was looking for an effective, all-natural mosquito repellent, though she was also curious how to prevent tick bites. In other words, she wanted something that would work and is not DEET.
The U.S. Environmental Protection Agency has reviewed DEET several times and maintains it’s generally safe to use, though they acknowledge it causes “skin irritation” in some users.
Yes, some parents have reported nervous-system problems in children exposed to DEET. Official sources maintain that this is due to not following instructions and warnings for proper use. (Popular Science notes that the number of severe cases is extremely low, and the problems can’t be conclusively linked to DEET use anyway.)
But Renée’s question got me wondering: How well DO insect repellents work against ticks? (Ticks are, after all, more closely related to spiders than mosquitoes.)
News reports of this year’s especially-bad tick season, which usually end with something like “apply bug repellent,” weren’t very helpful. And family-camping season is rapidly approaching.
So I did some research. This is what I learned.
Unless you’re new to tick-borne illnesses, you probably already know the standard advice. But it’s worth repeating anyway: To protect your kids from tick bites,
- Don’t take them tromping through the underbrush. When you and yours must be outside, stick to shorter grass and stay on the center of trails.
- Wear long pants and long sleeves in light colors, topped off with a hat or bandana.
- Tuck pants legs into light-colored socks.
- Do a tick check as soon as you’re done outside, paying special attention to armpits, groin, and other warm areas where ticks like to hide. Then run those play clothes through a hot dryer for 10 minutes, to kill any ticks on them.
- Protect your pets against ticks as well, and check them after they’ve been outside.
So, once you’ve covered those bases,
Which insect repellent will protect your kids from tick bites?
Here’s a rundown of the more common insect-repellent active ingredients, and how well they work against ticks and mosquitoes:
With one exception (see below), these provide little protection from mosquitoes. In tests conducted by the independent organization Consumer Reports, repellents based on natural oils generally repelled mosquitoes for only 30-60 minutes.
Moreover, as American Academy of Pediatrics physicians have noted, these oils can cause severe allergic reactions in some users, and we don’t really know how well they work against ticks. The Center for Wilderness Safety deems them ineffective tick repellents.
While Consumer Reports testing found that some natural-oil formulas offer limited tick protection, personally, I’d rather use something that will work against ticks AND mosquitoes.
This was the only naturally-based ingredient that Consumer Reports gave decent marks for repelling both ticks AND mosquitoes. This makes it an encouraging all-natural option.
With one major caveat: According to the Centers for Disease Control and Prevention, oil of lemon eucalyptus isn’t safe for kids under three years, because of possible skin irritation or allergic reaction. (That would include my friend Renée’s kids. Sorry, Renée!)
This active ingredient has been widely used in Europe for over three decades now. While it does well on tests against ticks and one type of mosquito, it does poorly against another common mosquito variety.
Again, though, there are caveats. One, you need to make sure the concentration of IR3535 is high enough to be effective; lower concentrations (7.5%) don’t protect well at all. Second, avoid products containing IR3535 (or any bug repellent) plus sunscreen. Because sunscreen needs to be reapplied more often than bug repellents, you’ll either come up short on sun protection, or overdose on repellent.
Picaridin (aka KBR 3023), the top-selling repellent ingredient in Europe and Australia, is still relatively new to the United States. Nonetheless, it’s the only non-DEET repellent that the American Academy of Pediatrics even mentions as a DEET alternative.
Whether it works against ticks depends not so much on who you ask, as on the concentration you’re using. According to Consumer Reports, products containing 20% picaridin repel both mosquitoes and ticks for much longer than those with lower concentrations.
And while opponents of DEET will like that picaridin won’t melt plastics or your clothes – as DEET has been known to do – it hasn’t been around as long as DEET, so it hasn’t been studied as thoroughly.
DEET, first invented by the U.S. Army in 1946, is the most-studied bug repellent around. It’s widely considered safe for human use and effective at repelling mosquitoes. Popular Science calls it “the best insect repellent humans have ever invented.”
But I still wondered: Does it effectively repel ticks?
DEET and ticks
The answer, again, is “it depends.” Consumer Reports recommends products containing 15-30% DEET for long-lasting tick prevention. But one 25% DEET product they tested did poorly at long-term tick control, and concentrations less than 10% also didn’t protect as long.
And this is where it gets tricky, if you’re a parent who wants to protect your kids from tick bites:
- The higher the percentage of DEET (up to 30%, at least), the longer it’s effective at repelling mosquitoes and ticks.
- However, The American Academy of Pediatrics recommends DEET only for children older than 2 months. Health Canada recommends only very limited use for children age 6 months-2 years, and none for kids under 6 months.
- It’s also generally advised that parents apply DEET products to children no more than once per day.
- And according to the medical professionals behind UpToDate.com, you need to reapply DEET (at concentrations of at least 20%) every two hours for effective tick protection.
- Furthermore, Health Canada recommends no more than 10% DEET concentrations for children ages 2-12. Even though the Canadian Paediatric Society acknowledges this concentration is too low to repel ticks for very long.
So yes, the Appalachian Mountain Club tells its members that DEET trumps picaridin against ticks.
But the more I read, the more I found an even better option:
The BEST way to protect your kids from tick bites is to
Dress them in permethrin-treated clothing
- This is the strategy the University of Rhode Island’s Tick Encounter Resource Center recommends.
- It’s what the U.S. Centers for Disease Control and Prevention recommends (along with using DEET and staying in the center of trails).
- It’s what the U.S. Department of Defense uses for its troops, along with DEET repellent on skin.
But if you have to choose between DEET on your skin and permethrin-treated clothing, choose permethrin. According to Tom Grier, a Lyme Disease researcher at University of Minnesota-Duluth Medical School, “permethrin wins hands-down.”
As American Academy of Pediatrics doctors and many others have noted, it’s “the most effective repellent for ticks.” Whereas skin repellents act to repel ticks, contact with permethrin actually KILLS the ticks in 5-30 seconds.
Permethrin is a synthetic version of a naturally-occuring insecticide found in chrysanthemums. Not only does it kill ticks, it also kills mosquitoes. So effectively, in fact, that permethrin-treated clothes are what the CDC recommends for protection against the Zika virus.
Even better, it’s non-toxic to humans once dried. And honestly, the CDC’s cautionary notes on permethrin sound pretty common-sense to me, anyway: don’t get the liquid form into your eyes, on your skin, or into your lungs, because it could cause irritation. (Worth repeating: Permethrin is for your clothing, NOT YOUR SKIN.)
Also worth noting: while drying, it’s toxic for cats. And though it’s great for killing mosquitoes and ticks, it’s also highly toxic to honeybees, fish, and aquatic life more generally. So skip treating those swimsuits before your next beach trip.
How do I get permethrin-treated clothing?
There are three ways you can get permethrin-treated clothes for your summer adventures:
- Buy clothing already treated with permethrin. Look for items including the names Insect Shield, BugsAway, or Insect Blocker. Commercially-treated items will retain their repellency for 60-70 washings. (One Step Ahead makes Bug Smarties clothing, a line of commercially-treated clothes for kids up to size 8.)
- Send your favorite clothes away to Insect Shield to have them commercially treated for you. This costs $8-10 US per item for most types of clothing (the more pieces you send them, the lower the per-item cost), and the turnaround time is pretty fast. While this may seem pricey, you’ll end up with the same commercial-grade protection as if you’d bought new permethrin-infused clothes.
- Treat your clothes yourself at home. Several companies sell DIY permethrin-treatment spray, including Sawyer. DIY treatments will only last 6 weeks/6 washings, but you may find this more cost-effective for kids’ summer wear, especially if you tend to acquire your children’s attire “gently-used.”
Now that you know how to prevent tick bites with permethrin, see my next post for more on applying your own permethrin to clothing. I recently tried doing this for the first time, and so far we’re pleased with the results!
And here’s to a summer with no tick bites! (Or mosquito bites, for that matter!)