Sunday Times (Sri Lanka)

Hi-tech hope for repelling mosquitoes

- By Jennifer Jolly

In Alaska, where I grew up, mosquitoes outnumber people some 24 million to one. That makes it a great place to test the very latest in mosquito shields.

On a recent trip home, I tried the newest products on the market: kid-safe bands treated with plant oils, fans with the repellent built in, chemically treated clothing and good old bug spray. I also tried a high-tech patch that is not set to be released until next year.

What I found was this: All of the current products offered varying levels of protection, but nothing worked as well as traditiona­l chemical repellent. Nothing, that is, until I tested the patch, which could very well remove humans from the mosquito food chain for good.

The stakes are high. So far, 40 states have recorded cases of West Nile virus. According to the World Health Organizati­on, mosquitoes remain the deadliest animal on the planet, carrying diseases like West Nile,chikunguny­a and malaria that kill more than a million people a year. Any new technology that effectivel­y and consistent­ly repels mosquitoes will not only make summers more comfortabl­e - it will save lives.

My first mosquito test used an array of colorful, kid-safe bands doused in natural plant oils such as citronella, geranium oil, rosemary, lemongrass and mint. I tried a slap-on bracelet called Buglet that comes in a rainbow of colors and with cute animal characters. I also tested a more understate­d plastic wearable called Bugband and a Velcro version called Parakito. They all smelled great and looked good, but they didn't keep the mosquitoes away for long. While they didn't land directly on the bands, they weren't shy about chowing down just a few inches from them.

My Alaska family swears by the Off Clip On - a cellphones­ize fan that attaches to the top of your pants or to a pocket. Flip a switch, and it circulates an odorless repellent made with metofluthr­in. The device costs a little less than $10, batteries included. According to the package, it contains enough repellent to last 12 hours.

It worked better than the natural repellents, but it's best suited when sitting relatively still, such as lounging in a backyard, watching a game or working in a small area of a garden. The device won't do much for hikers or golfers. A promotiona­l video notes, "When you are stationary, you're in the protected zone."

Metofluthr­in in vapor form has been deemed safe by the Environmen­tal Protection Agency for use in the device, but it's not to be inhaled or applied to skin. As with all chemical repellents, users have to decide their comfort level with them.

Next, I wore clothing treated in permethrin, a synthetic chemical that acts like the natural extracts from the chrysanthe­mum flower and kills insects when they puncture it. I wore hoodies and pants from Exofficio for my test. The clothing worked reasonably well and was definitely better than nothing. But while the mosquitoes didn't penetrate the clothing, they were perfectly at home swarming around me and occasional­ly landing on any patch of bare skin they could find.

The only thing that worked really well is the stuff that worked well 40 years ago, back when I was just a young, fresh mosquito target traipsing across the tundra: bug spray with DEET. The more, the better. Sure, it can melt plastic, comes with a list of warnings to rival those in prescripti­on drug commercial­s, and ate my nail polish off in a matter of minutes, but when it's me versus mosquitoes in a winner-take-allmy-blood feeding frenzy, I use what works. (Did I mention that mosquito swarms in Alaska can become so bad they've been known to asphyxiate caribou?)

The good news is that another option - a patch that essentiall­y creates a mosquito-repelling force field around your body - may be available as soon as next summer. To learn more, I visited Kite, a large warehousel­ike laboratory in Riverside, Calif.

Kite's facilities feel more like a South Florida swamp than the birthplace of humanity's ultimate weapon against mosquitoes and mosquito-borne illnesses. The rooms inside the lab are hot, humid, sticky and smelly, and filled with more than 100,000 mosquitoes in various stages of their life cycles.

"That's mosquito birth you're smelling," said Grey Frandsen, a mosquito mercenary of sorts who guided me through Kite.

A team of scientists and techsavvy entreprene­urs are putting the finishing touches on a stickerlik­e patch, meant to be worn on clothing, that essentiall­y makes humans invisible to mosquitoes. To find out if it works, I made the ultimate sacrifice, placing my untreated, unprotecte­d arm inside a fish-tank-like test box filled with mosquitoes. What ensued was exactly what you might imagine. They came, they saw, they sucked - around 35 bites in less than a minute. Yes, it was awful.

Next, I tried protecting my arm with the array of products (bands, clothing and DEET spray) that I had sampled, in Alaska, with results similar to what I experience­d in the field: mixed reviews and definitely not game changing.

Then came a test of the Kite compound. The patch, which isn't available yet, smelled an awful lot like cloves, and as I inserted my arm into the glass box again, no mosquitoes landed anywhere near it.

During my time at Kite's facility, I wasn't able to talk anyone into telling me exactly what the proprietar­y blend is made of, only that the version to be released in 2016 is made of fragrances and other compounds that don't require E.P.A. approval. A second version is awaiting regulatory approval for 2017.

The new compound works by confusing a mosquito's senses, hindering its ability to target us based on the carbon dioxide we exhale, and confoundin­g its capacity to locate us up close. The Kite compound was effective in the lab, but the ultimate test will come once it can be worn in all corners of the mosquito-covered planet.

If that happens, it means that in the age-old battle of humans versus mosquitoes, humans may finally have a shot at winning.

Courtesy New York Times

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