NMSU research reveals mosquito repellents that work best
Writer: Taylor Vancel, 575-646-7953, firstname.lastname@example.org
Just as the first mosquitoes of the season are making an appearance, New Mexico State University researchers are sharing results of six months of testing on 11 different mosquito repellent products.
Stacy Rodriguez, laboratory manager for NMSU’s Molecular Vector Physiology Lab, discusses testing wearable mosquito repellents inside the wind tunnel at NMSU with graduate student Kristina Gonzales (right), while undergraduate student Hae-Na Chung looks on from inside the enclosure behind them. Chung and Rodriguez will sit inside the enclosure with caged mosquitoes to track the mosquito’s attraction for them while wearing wearable repellent devices to determine their effectiveness. (NMSU photo by Minerva Baumann)
The New Mexico Department of Health announced on May 17 that the yellow fever mosquitoes already have been identified in Dona Ana County. Last summer, this type of mosquito, which can carry Zika and other viruses, was found in Doña Ana, Eddy, Sierra, Lea, Chaves and Roosevelt counties.
“Many people seem to be attracted to the most convenient and appealing mosquito repellents, including the newer wearable devices,” said Stacy Rodriguez, laboratory manager for NMSU's Molecular Vector Physiology Lab in the College or Arts and Sciences. “I really wanted to find out what products actually had an effect on keeping mosquitos away.”
Rodriguez, lead researcher on this project, published her newest study in the Journal of Insect Science.
She tested five spray-on products, five wearable repellent devices and one candle against the yellow fever mosquito.
“When we walk into a store we see many mosquito repellents right by the registers, so they become an impulse buy,” said Rodriguez. “But what we’ve found is that some of these products have little to no effect on keeping mosquitos away.”
Rodriguez tested wearable devices Off! Clip-on, Personal Sonic Mosquito Repeller, Mosquitavert, Mosquito-NO! and Invisiband. Spray-on repellents tested were Cutter Lemon Eucalyptus, Kids Herbal Armor, Avon Skin-So-Soft Bug Guard Plus Picaridin, Repel Sportsmen Max Formula and Ben’s tick & Insect Repellent. For the experiment, Rodriguez had volunteers wear different wearable devices and sprays. A Cutter Citro Guard candle was also tested. The candle was placed downwind next to the test subject.
Prior to the experiment, volunteers were asked not to bathe or use personal hygiene products in order to create a baseline level of mosquito attraction.
The experiment was conducted at NMSU’s low-speed wind tunnel. Approximately 50–125 female mosquitoes were collected and placed in a mesh cage at various distances from the volunteer inside a Plexiglas enclosure. One person was placed upwind of the cage filled with mosquitoes and the mosquito movement towards or away from the person was recorded.
Before every repellent evaluation, control tests were done to determine overall attraction the mosquitoes had to the volunteers on that particular day.
The results of Rodriguez’ recent study confirms that certain active ingredients make certain repellents more effective than others. Products containing DEET and those with Oil of Eucalyptus were determined to be most effective.
The only wearable device tested that repelled mosquitoes was the Off! Clip-on device. The Off! Clip-on not only repelled mosquitoes, but also killed them.
“None of the bracelets we tested caused any significant reduction in mosquito attraction,” Rodriguez said. “Although the active ingredients in some bracelets may be mosquito repellents, the concentrations released by the bracelets are most likely too low to have an effect. Based on our results, we concluded that these bracelets in general do not offer adequate protection from mosquito bites.”
The citronella candle also had no effect.
“Not all repellents are considered equal,” Rodriguez said. “I just want people to know that there is much more to their mosquito repellent than just the brands. They need to check the active ingredients to see which will actually work.”
Read full results of each tested brand and learn more about this NMSU mosquito repellent research in The Journal of Insect Science at http://nmsu.life/1c.