Big Question: Do mosquitoes really prefer some people over others?
The expert: Dr. Edward Blumenthal, assistant professor of biological sciences
“We all know people who are mosquito magnets — attracting all of the mosquitoes and getting eaten alive at a barbecue. Perhaps you are unlucky enough to be that person. Multiple scientific studies have shown that this really does happen: When given the choice, mosquitoes will consistently land on, and bite, certain people and not others.
“Why mosquitoes show this preference, however, is still unclear. The Internet is full of information on this subject — mosquitoes prefer blondes over brunettes, children over adults, etc. — but very little of this is based on reliable scientific data. We know that mosquitoes identify their targets through multiple sensory modalities, by detecting carbon dioxide, heat, odors and visual cues. Complicating the issue is that different species of mosquito use these cues differently and have different preferences. For example, the African mosquitoes that carry malaria will bite pregnant women twice as often as nonpregnant women — most likely because pregnant women produce more heat and carbon dioxide — but other species of mosquito don’t show this preference.
“The color of your clothing has been shown to make some difference — mosquitoes prefer dark colors that don’t reflect much light — but keep in mind that most mosquitoes are active after dark, when the color of your clothes won’t make much difference. The most important differences among us are probably in the odors we give off, and unfortunately we humans emit so many smelly chemicals that scientists haven’t yet figured out which ones are most attractive or repellent to mosquitoes. The good news is that recent work using molecular biological approaches is beginning to tease out the smells that are most important to mosquitoes. One more thing to keep in mind going into this holiday weekend: A recent study has shown that people are significantly more attractive to mosquitoes after drinking beer!”
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