A clip-on repellent device is deemed effective in warding off bites from the Aedes aegypti mosquito, which is the primary vector of the Zika virus and other tropical infections chikungunya, dengue and yellow fever.

The OFF! Clip-On prevents mosquito bites by releasing a vapor-like insecticide through a battery-operated fan, producing an insecticide “cloud” around the device wearer.

Researchers Christopher Bibbs and Rui-De Xue of Florida’s Anastacia Mosquito Control District conducted an outdoor test to see how the device will work against hungry mosquitoes.

They discovered that the clip-on caused high mosquito death and knockdown rates up to 0.3 meters away from the device – considered enough to protect the wearer. “Knockdown” refers to an acute paralysis that knocks the insect out of the air.

The results came as a surprise for them.

“Skepticism is inherent to the trade. But it was nice for a change of pace that one of these devices could actually do some good,” said Bibbs.

Bibbs was referring to vector-control products that do not work effectively for consumers, including repellent bracelets, bug zappers and other novel creations that come and go.

“Repellent,” however, may not describe the product sufficiently, added Bibbs, as its insecticide cloud also managed to kill or knock the mosquitoes down.

“In light of the recent evidence, I have taken more to thinking of such devices as ‘vapor active insectides,’” he explained, deeming “spatial repellent” as less than appropriate for the clip-on’s actual function.

The researchers see great promise in this line of devices, given that mosquitoes tend to be delicate pests. The low volume of vapor released from the clip-on adequately kills them if they are unfortunate enough to fly through the insecticide cloud.

The findings were published in the Journal of Medical Entomology.

The World Health Organization (WHO) already declared the Zika virus outbreak a global emergency constituting a public health risk through a worldwide spread.

The WHO called for “a coordinated international response” to minimize threats in affected countries – mostly Brazil and at least 14 other Latin American countries and territories – and reduce transmission potential.

Photo: U.S. Department of Agriculture | Flickr