Speaker 1: Welcome to brain Stuff production of I Heart Radio. Hey
Speaker 1: brain Stuff, Lauren bog Obam here with a classic episode
Speaker 1: from our previous host, Christian Sagar. I pulled this one
Speaker 1: out today because the brain Stuff headquarters are in Atlanta,
Speaker 1: and here in Georgia, we're getting our first mosquitoes of
Speaker 1: the year. For me, that means I got a bunch
Speaker 1: of bites when I ventured outside for a socially distant
Speaker 1: walk yesterday. But are some people immune to mosquitoes? Hey
Speaker 1: brain Stuff? It's Christian Sager. If you're like most people,
Speaker 1: you hate mosquitoes. They're kind of the Andy Dick of
Speaker 1: the insect world, annoying and in some cases dangerous. If
Speaker 1: we rate animals by the number of deaths they cause,
Speaker 1: these little bloodsuckers topped the charts by a wide margin.
Speaker 1: And this is due to their transmission of malaria and
Speaker 1: other harmful diseases. And whether your next mosquito bite causes
Speaker 1: serious illness or intense frustration, and we can all agree
Speaker 1: mosquitoes are just the worst. But are some people immune
Speaker 1: to mosquito bites? First, let's be clear, mosquito bites aren't
Speaker 1: actually bites. When a mosquito lands on you. She uses
Speaker 1: her probosis it's a long, double tubed mouthpiece to pierce
Speaker 1: your skin and get at the blood underneath. And yes,
Speaker 1: that's a sheet. Every single mosquito that has ever bitten
Speaker 1: you has been female. They bite you because they need
Speaker 1: a protein in your blood to develop their eggs. When
Speaker 1: a mosquito uses her antenna to sense the warm blood
Speaker 1: beneath your skin and then pops her probosis in to
Speaker 1: tap your capillaries, one of those tubes injects saliva while
Speaker 1: the other one withdraws blood. The saliva contains enzymes that
Speaker 1: act as a mild painkiller and thins the blood to
Speaker 1: prevent clotting. Your body interprets these enzymes as foreign invaders
Speaker 1: and produces histamine. Histamine binds to scepters in the bite area,
Speaker 1: dilating local blood vessels. This increased blood flow summons more
Speaker 1: white blood cells, and when you get too much histamine,
Speaker 1: the bite area can swell and redden creating what's called
Speaker 1: a wheel. Yeah, wheel, that's the word of the day. Now,
Speaker 1: each person will react to a bite differently, and your
Speaker 1: allergies will vary. So what makes a mosquito choose a
Speaker 1: certain person well. There are a number of factors, one
Speaker 1: of the biggest being that there are more than three
Speaker 1: thousand known varieties of mosquitoes and they're not all looking
Speaker 1: for the same thing. For those that dig a nice
Speaker 1: sip of human blood, smell, body temperature, and genetics play
Speaker 1: huge roles. According to scientists at Rotterdam Research, each human
Speaker 1: body can produce anywhere from three hundred to four hundred
Speaker 1: distinct chemical odors, some of which are bug magnets and
Speaker 1: others they might be bug repellent. Research from a chemist
Speaker 1: named ul Ric Burner shows that mosquitoes are particularly fond
Speaker 1: of carbon dioxide that's released from exhalation and the skin,
Speaker 1: and they also like lactic acid, which is present on
Speaker 1: our skin after exercise. Now, drinking beer, being pregnant, and
Speaker 1: being a bigger person can all also make you more
Speaker 1: attractive to mosquitoes. Diet and blood type surprisingly don't seem
Speaker 1: to matter so much. Everybody has these yummy chemicals on
Speaker 1: their body, but it seems that the people mosquitoes avoid
Speaker 1: produce higher amounts of repellent chemicals. Dr James Logan from
Speaker 1: Rotterdam set up a pretty weird experiment to see if
Speaker 1: he could find these all important repellent chemicals. His team
Speaker 1: separated people into two groups, mosquito favorites and mosquito mez.
Speaker 1: They put these folks in body size foil bags to
Speaker 1: collect their odors for two hours, and they used a
Speaker 1: chromatograph to analyze the chemicals they had collected, and hooked
Speaker 1: electrodes up to mosquito antenna to see what the bugs
Speaker 1: thought of each smell. They found about seven or eight
Speaker 1: made a difference. These odors were present insignificantly different quantities
Speaker 1: between those people who were attractive to mosquitoes and those
Speaker 1: who weren't. Their study, published in the Journal of Medical Entomology,
Speaker 1: cited two chemicals as significantly repellent, one called six methyl
Speaker 1: five hepton to one, which apparently smells of nail polish remover,
Speaker 1: and another called jennal acetone, which has a kind of
Speaker 1: floral odor. As of this recording, the race to use
Speaker 1: these and other chemicals as a new superbug repellent is
Speaker 1: in full swing. So you probably know that bacteria is
Speaker 1: largely responsible for the various smells of the human body.
Speaker 1: Each human being is home to a unique mix of
Speaker 1: trillions of microbes. It's sort of like a fingerprint now
Speaker 1: our genes may play a large role in determining what
Speaker 1: sort of microbial life forms we end up posting in.
Speaker 1: A team led by doctor Manuela Fernandez Grandin tested the
Speaker 1: heritability of attractiveness to mosquitoes using twins. The twins would
Speaker 1: put a hand into either end of a sealed dome
Speaker 1: along with twenty female mosquitoes. Now don't worry, they weren't
Speaker 1: allowed to bite. Researchers gave each subject an attractiveness score.
Speaker 1: Compared to the other hand, identical twins had consistently more
Speaker 1: similar scores compared to fraternal twins, so jeans do seem
Speaker 1: to play a role. This may be tough news for
Speaker 1: the twenty or so of people that mosquitoes find particularly attractive.
Speaker 1: If you're one of the local mosquito's favorite dishes, remember
Speaker 1: to keep some kind of bug repellent with you and
Speaker 1: to wear long sleeves and pants if the weather allows,
Speaker 1: especially in areas of the world where these bugs carried
Speaker 1: diseases like malaria or denga. And I suppose there's a
Speaker 1: little light at the end of this mosquito net tunnel here,
Speaker 1: some people do have a chance of building up a
Speaker 1: tolerance after repeated mosquito bites, but for others, the allergy
Speaker 1: just gets worse. Today's episode was written by Ben Boland
Speaker 1: and produced by Tyler Claang. To hear more from Ben,
Speaker 1: including jokes that have aged better than that, Andy dick
Speaker 1: One at the top, a tune into his podcast Ridiculous History,
Speaker 1: and of course, for more on this and lots of
Speaker 1: other biting topics, visit house to works dot com. Brain
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