What scientists say keeps mosquitoes at bay

Mosquitoes hunt us by following our exhaled carbon dioxide. They are attracted to the lactic acid in our sweat and to certain chemicals in our breath. Scientists recommend using mosquito repellents and staying indoors at dawn and dusk when mosquitoes are most active.

What scientists say keeps mosquitoes at bay

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Since humans have existed, mosquitos have buzzed around looking for a bite.

Conor McMeniman is an assistant professor of microbiology and immunity at the Johns Hopkins Bloomberg School of Public Health in Baltimore and Johns Hopkins Malaria Research Institute.

Mosquitoes are often the cause of death, as they transmit diseases like West Nile virus, West Nile fever and dengue fever.

They can still be a nuisance, even if they don't transmit these diseases. What attracts mosquitoes, how they hunt, and what scientists suggest to keep them away are all explained here.

Mosquito bites: a scientific perspective

Mosquitoes are often found drinking plant juices and nectars. They can even be seen pollinating flowers. When it comes to the female mosquito producing eggs, they need extra protein. They get this by drinking blood.

McMeniman explained that when a mosquito bites it is actually probing the skin with its mouth to find a blood vein. The mosquito, once it finds the blood vessel, sucks it up like it was drinking bubble tea.

The mosquito has an advantage in that it can drink quickly, then fly off unnoticed. He said that mosquitoes use a cocktail of proteins to spit on the skin. These proteins act as anticoagulants and painkillers, which prevent the blood from clotting. Itching and discomfort are only felt after mosquito bites, as our bodies react in an inflammatory way to the chemical cocktail.

Different people react differently to mosquito bites. One person may leave a barbeque with just a few pimples, while another is left nursing dozens and dozens of silver-dollar-sized welts the next week.

McMeniman explained that the perceived attractiveness of mosquitoes to you may not be correlated with your actual attractiveness to them. Some of it is determined by your perception of how you react to mosquitoes, and whether or not you itch.

What attracts mosquitoes

McMeniman's study published in Current Biology shows that certain people are actually mosquito magnets. Mosquitoes respond differently to each person's unique body odor, and some are more appealing than others. It's not easy to pinpoint what makes certain people more attractive to mosquitoes.

McMeniman explained that a number of factors could influence the composition and scent of your body, including your diet, genetics, and physiology. All of these factors could influence the type of molecules released by the body, and the microbiome which lives on our skin.

At this stage, it is not possible to sell a body spray that mimics the odor of people who mosquitoes avoid. He said that they were still attempting to understand the chemistry behind this process.

Researchers are still exploring the specifics of what scents attract mosquitoes, but there is a pattern in how the insects find us.

McMeniman explained that mosquitoes can detect thermal cues from the skin when they are close enough. Carbon dioxide is one of the main scents that attract mosquitoes from a distance.

Dr. Kristen Healy is an associate professor of Entomology at Louisiana State University, and the president of the American Mosquito Control Association. There have been many studies that show CO2 released by our exhalation, especially in large groups, can attract mosquitoes. The body heat and sweat seem to also play a part.

Healy's own experience has confirmed that this hypothesis is true. She said that if she is active and sweating, it will be noticeable to her. Mosquitoes can detect the extra odors.

Over the years, several scientific studies have identified possible keys to mosquito attraction. Some have shown that people who drink beer are more likely to be bitten. Others have suggested that certain colors, such as red, may be particularly attractive to mosquitoes.

McMeniman stated that it would be useful to scale up these studies to see how general the findings are across various hosts. You shouldn't toss out your red shirts or all of your beer until then.

How to avoid mosquito bites

There are many devices and sprays on the market that claim to repel mosquitoes. This is probably due to the unsolved mystery surrounding the attraction of mosquitoes. Healy stated that newfangled gadgets like ultrasonic repellent devices were not backed by science and research, but are simply on the market. I would never believe a product which claims to be 100% effective in killing mosquitoes.

The devices that spray repellents over a large area are effective. However, McMeniman noted that they are actually insecticides. They have passed the EPA's (US Environmental Protection Agency's) registration standards. You are still walking in a cloud.

Healy & McMeniman suggest more tried-and-true methods.

McMeniman advised that it is important to cover up as much skin as possible in the summer and use an insect repellent with ingredients like DEET and Picaridin. He recommends the oil of lemon-eucalyptus for those who prefer botanical products.

If you want to keep mosquitoes away from your home, screen your windows and use a fan or an air conditioner during the night. To prevent mosquitoes from hatching, remove debris and drain any standing water from your yard every week.

There is no magic bullet to protect you against mosquito bites. No matter how tantalizing the results of various studies are, there is no magic diet, color or soap scent that will keep mosquitoes at bay.

Mosquitoes, like all other insects in the world, are part of our natural environment. We must learn to live with them. Use a bug spray that is effective and reapply as necessary.