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Q. Dear Umbra,

I’m seeing a lot about Lyme disease and West Nile in the media — it’s enough to make a person freak out. While I’m not a big fan of bug spray, it seems like a requirement for leaving the house these days. What are the safest options? Is DEET ever OK?

Jen H.
Ithaca, N.Y.

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A. Dearest Jen,

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Remember the days when summertime meant arms and legs covered with scrapes and scratches and mosquito bites? In the Fisk household when I was coming up, that was a sign of long days well spent. But in this day and age, those bites would practically be grounds for a call to protective services. Partly that’s because society has gotten weirder about the outdoors. But it’s also because we seem to be facing more scary diseases.

Do I need to point out that a big reason we’re having to worry about Lyme, West Nile, dengue fever, and other “vector-borne diseases,” as they’re called, is climate change? I might need to point that out. Here goes: The climate is warming due to human activity. The warmer climate makes some places more inviting for critters, creating welcoming habitats where they can breed and live happily. Some of those critters carry disease. Ergo, we humans suddenly face the possibility of encounters with new diseases — even if we are living in the same old places.

Oh, and this is not just an issue in the summertime. Ticks, for instance, which can carry Lyme disease, have been more active in the winter in recent years. Milder winters also mean higher survival rates for ticks and for the mice that are their hosts. Good news all around — if you’re a tick.

It seems that Lyme and West Nile and other signs of the end times are here, and deal with them we must. So what’s the best way to protect ourselves? It all depends.

In a new guide to bug repellents, the Environmental Working Group says every product has pros and cons. What we choose to use should depend on whether we are an adult or a child, which pests we wish to protect against, and what activities we have planned. EWG has helpfully dumbed the entire dilemma down for us — check out the big, colorful buttons on this page — and I for one am grateful. I encourage you to poke around the guide.

Guess what else the smarties at EWG found out? I’ll let them tell you in their own words: “Among the four repellent chemicals EWG found to be top picks is DEET, which is widely used but much maligned. DEET’s safety profile is better than many people assume. Its effectiveness at preventing bites is approached by only a few other repellent ingredients.” They continue with a note of caution: “DEET isn’t a perfect choice, nor the only choice. But weighed against the consequences of Lyme disease and West Nile virus, we believe it is a reasonable one.” However, they caution against using any repellent containing higher than 30 percent DEET.

If you’re not keen on slathering your skin in chemicals, you can take other steps:

  • When possible, use physical barriers to keep the bugs away. When you take walks in wooded or grassy areas, wearing long sleeves and tucking your pants into your socks can be very effective, if not exactly fashionable. (Be sure to check yourself for ticks after such explorations.) Netting or screens can also come in handy in mosquito-prone places.
  • Don’t leave standing water in your yard; it can become a breeding ground for mosquitoes.
  • Reduce exposure to mosquitoes by heading inside at dusk, when they like to get buzzy.
  • Buy or make bug potions with natural ingredients. Essential oils like eucalyptus, lemongrass, and tea tree can work wonders, and recipes abound online.

You could, of course, never leave the house, but I do believe the benefits of going outside still outweigh the risks.