How To Kill Mosquitoes, Not What You Think
Summer is the time when many people want to know the best way to kill mosquitoes, or at least avoid them. Although you can spray them and squash them, researchers at Ohio State University and other facilities have discovered another way to kill mosquitoes, and the discovery may lead to insecticides that work in a new way.
Did you know mosquitoes pee?
Mosquitoes transmit disease; or more specifically, the female mosquitoes are the bearers of disease, since only the females feed on humans and animals and ingest their blood. Once a female mosquito becomes infected, she can pass along the disease during her short life time, which is only a few weeks.
Researchers are especially interested in stopping mosquitoes because they can transmit a number of deadly diseases, such as malaria and dengue fever. That’s a major reason why researchers at Ohio State’s Ohio Agricultural Research and Development Center (OARDC) are happy to report they discovered a chemical that hinders the ability of mosquitoes to pee.
Why is this important? Because when scientists found a way to stop mosquitoes from peeing (excreting urine), it “leaves mosquitoes unable to fly and in some cases severely bloated, all of which would lead to a shorter lifespan for the mosquitoes.”
Biting mosquitoes need to immediately eliminate the fluids and salt they ingest, and so they pee on their host, even while they are still on the skin. However, if they are treated with a chemical that interferes with their ability to urinate, they will less chance to escape and also have a shorter lifespan.
Specifically, the researchers found that the chemical hinders the function of potassium channels, which in turn prevents the insects from releasing urine. This information now allows scientists to go in search “of similar chemicals that will show a high potency for perturbing potassium channels in mosquitoes, but not those in humans and other animals,” according to the study’s leader, Peter Piermarini, assistant professor of entomology at the Wooster campus of Ohio State’s OARDC.
How to deal with mosquitoes
Mosquitoes are a minute problem with huge consequences. In addition to the risk of malaria and dengue fever, mosquitoes can also transmit West Nile virus, yellow fever, Rift Valley fever, and various forms of encephalitis.
So what is an effective way to prevent these insects from biting? Most of the chemicals used to control mosquitoes are insecticides that attack the nervous system, such as DEET (N,N-dietyl-meta-toluamide), which has been recommended by many experts for years.
However, mosquitoes have become less sensitive to DEET and other insecticides, which places humans at greater risk of acquiring the diseases these insects can transmit. In addition, although the Environmental Protection Agency insists proper use of DEET will greatly reduce the chance of toxicity, some people avoid the chemical because of possible adverse effects, such as nausea, disorientation, confusion, convulsions, and behavioral changes.
Natural approaches to keeping mosquitoes away include
- Use of dryer sheets that contain beta-citronellol and linalool
- Use of essential oils and their components, including citronella, linalool, and geraniol in candles and diffusers
- Rubbing crushed leaves of lemon balm, basil, lemon grass, or lemon thyme on the skin. Protection against mosquitoes lasts only about 30 minutes before reapplication is necessary
- Combine 1 tablespoon of vanilla extract in 8 ounces of water and put in a spray bottle. Spritz on your skin to detract mosquitoes
Mosquitoes are more than a nuisance: they are tiny couriers of diseases that affect hundreds of millions of people every year. The discovery of a new way to kill mosquitoes by preventing them from peeing may prove to be a breakthrough in mosquito control.
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Stanczyk NM et al. Aedes aegypti mosquitoes exhibit decreased repellency by DEET following previous exposure. PLoS ONE 2013; 8(1): e54438