Some folks seem to be magnets for mosquitoes, while others rarely get bitten. What makes the little buggers single you out and not the guy or gal you're standing next to at the Memorial Day backyard barbecue?The two most important reasons a mosquito is attracted to you have to do with sight and smell, says Jonathan Day, a professor of medical entomology at the University of Florida in Vero Beach. Lab studies suggest that 20 percent of people are high attractor types, he says.Mosquitoes are highly visual, especially later in the afternoon, and their first mode of search for humans is through vision, explains Day. People dressed in dark colors -- black, navy blue, red -- stand out and movement is another cue.Once the mosquito keys in on a promising visual target, she (and it's always "she" -- only the ladies bite) then picks up on smell. The main attractor is your rate of carbon dioxide production with every exhale you take. Those with higher metabolic rates produce more carbon dioxide, as do larger people and pregnant women.
Although carbon dioxide is the primary attractant, other secondary smells coming from your skin or breath mark you as a good landing spot.Lactic acid (given off while exercising), acetone (a chemical released in your breath), and estradiol (a breakdown product of estrogen) can all be released at varying concentrations and lure in mosquitoes, says Day. Your body temperature, or warmth, can also make a difference. Mosquitoes may flock to pregnant women because of their extra body heat.But with more than 350 compounds isolated from odors produced by human skin, researchers have barely scratched the surface behind a mosquito's preference for certain people, says Joseph Conlon, a medical entomologist and the technical advisor to the American Mosquito Control Association.Although it may all boil down to human odor and genetics -- studies of twins have revealed they tend to be attractive or repellant to mosquitoes in the same measure -- it's more complicated than that, suggests Conlon.He says the latest thinking is that it might not be about what makes people more attractive to mosquitoes, but what makes them not as repellant.
It could be that individuals who get less bites produce chemicals on their skin that make them more repellant and cover up smells that mosquitoes find attractive.Mosquitoes don't bite you for food, since they feed off plant nectar, Conlon explains. Females suck your blood to get a protein needed to develop their eggs, which can then send more pesky insects into the world to annoy you.But keep this in mind when you're outdoors this summer: Mosquitoes are more attracted to people after they drink a 12-ounce beer. It could be that people breathe a little harder after a cold one or their skin is a little warmer, suggests Conlon. But that won't stop him from having a brewski, even though he considers himself a mosquito magnet.Here are more fun facts about mosquitoes and bites provided by our experts:Aedes aegypti, the mosquito can transmit Zika virus, is present in the U.S. As our mosquito season approaches, Americans should know that preventing mosquito bites is about more that avoiding itchy red bumps.
Avoiding mosquitos this summer is about more than preventing itchy bumps. It’s about preventing serious disease. Americans in certain parts of the U.S. should be on higher alert than usual about mosquitos because of the ongoing Zika virus epidemic in Latin America and the Caribbean, experts say. And while the highest risk zones are in Florida and Texas, more of the U.S. may be at risk. The world’s scientists generally agree that the mosquito-borne virus can cause severe birth defects like microcephaly. And scientists such as Anthony Cornel, a medical entomologist at the University of California, Davis, say that the Zika virus outbreaks in nearby parts of the world should make people in high-risk mosquito zones in the U.S. more vigilant about repelling bites. Zika is primarily transmitted by the Aedes Aegypti mosquito, which has been spotted as far north as New York. "With the impending threat of Zika and possibly chikungunya [a similar virus carried by the same mosquito], people need to be more aware of the presence of Aedes Aegypti, because that’s the major vector,” Cornel said.
"We don't know, of course, if we’re going to get local transmission of these viruses, but the threat is there, and the threat is now increasing because of the spread of the mosquito." Researchers from the University of Arizona, the National Center for Atmospheric Research and other institutions put together a map of where the Aedes Aegypti mosquito live in the U.S: The Aedes Aegypti mosquito doesn't inherently carry Zika virus, but instead passes the virus from sick people to others. Female mosquitoes need blood to lay their eggs, and when they bite someone infected with Zika virus, they can pass on the disease to other people in later bites. The U.S. does not have any recorded cases of this kind of "local" Zika virus transmission, just cases of people bringing the disease back after traveling. This means most Americans have nothing to worry about when it comes to local Zika virus transmission. But because more than 300 people have brought Zika virus back from a trip, and some of them may live in areas where the Aedes Aegypti breed and are projected to thrive this year, there is a risk that Zika virus may become endemic in the U.S.
To start preparing for mosquito season, assess your personal mosquito risk. Ask yourself these three questions to make sure you know how to prevent bites: 1. Are you a mosquito magnet? It's not your imagination: Some people do get bitten more than others. A small 2015 pilot study comparing identical twins to fraternal twins found that mosquitoes were similarly attracted to identical twins, but approached fraternal twins at different rates. These findings establish a genetic basis for varying levels of mosquito attractiveness. Mosquitos also appear to be more attracted to some body odors over others, and research points to different potential reasons for this. A 2011 study found that the bacteria on one's skin could be affecting odor and thus mosquito attractiveness. Another theory, put forth in 2013, is that mosquitos have exceptionally sensitive ways to detect carbon dioxide, and can even detect CO2 from our skin’s surfaces. If you already know from past experience that you tend to get bitten more than the people around you, be vigilant.
Wear long sleeves and pants and use insect repellant with the active ingredients DEET, Picaridin, IR3535 or oil of lemon eucalyptus. Campers and travelers can also go one step further by treating their clothes, tents and gear with a product called permethrin, which is another strong option against mosquitoes. These repellents are also safe for pregnant and nursing women, and most children over two months old notes the CDC, but children under three years old should not use products with oil of lemon eucalyptus or its synthetic version, PMD. To protect children younger than two months, place them in an infant carrier covered with a mosquito net with an elastic edge. Unfortunately, the strategy of eating certain foods to repel mosquitoes doesn’t hold up in scientific experimentation. A randomized, double-blinded and placebo-controlled trial found that eating garlic didn’t repel them. Another 2005 trial confirmed that vitamin B supplements don’t help, either. Drinking beer makes people more attractive to mosquitoes, so take that into account when you’re hanging by the campfire.