Why Mosquitoes Love You, But Not Me

Mosquitoes are attracted to carbon dioxide, body odor, secretions, blood type, lactic acid and beer
people having a picnic outside on blankets
(Precision Vaccinations News)

If you are wondering what attracts mosquitoes to you and not other people this summer, you may be surprised that mosquitoes actually know who they like best.

When making a targeting decision, a female mosquitoes' choice is not random.

Most mosquitoes specialize on a few hosts and some individuals in a host population are preferred over others, reported Virginia Tech scientists in the journal Current Biology. 

This study confirmed what scientists already suspected …. that mosquitoes remember the taste and smell of human blood and often pick on individuals whose blood is “sweeter” to them.

“Unfortunately, there is no way of knowing exactly what attracts a mosquito to a particular human. Individuals are made up of unique molecular cocktails that include combinations of more than 400 chemicals,” explains Clément Vinauger, professor of biochemistry in the College of Agriculture and Life Sciences, in a press release.

This study shows that mosquitoes can rapidly learn and remember the smells of hosts and that dopamine is a key mediator of this process.

However, this study also proved that even if an individual is deemed delicious-smelling, a mosquito’s preference can shift if that person’s smell is associated with an unpleasant sensation.

Hosts who swat at mosquitoes or perform other defensive behaviors may be abandoned, no matter how sweet.

Here are several main things everyone should know in order to avoid or to lure these insects:

  • Carbon dioxide – mosquitoes are attracted to the carbon dioxide we exhale, both the scent and the amount. Every time we exhale, we release chemicals like lactic acid, octenol, uric acid and fatty acids that combine with CO2 to form our own unique carbon dioxide cocktail. This combination of scents is what clues mosquitoes that there is a human target nearby. Additionally, the more CO2 we emit, the easier we are to recognize. The scent and amount of carbon dioxide you exhale is unique to you and your genetics, and unfortunately, there isn’t much you can do to change your attractiveness other than mask your scent.
  • Body odor – bacterial colonies combined with sweat generate that sweet human scent we call body odor. Without the bacteria, our sweat would be odorless; with the bacteria, our sweat is one of the more attractive scents for mosquitoes. There are measures you can take like washing regularly to reduce body odor. However, be careful of fragrant scents that can also draw mosquitoes.
  • Secretions – about 80% of people secrete compounds known as saccharides and antigens through their skin and indicate blood type. Mosquitoes are magnets for secretors. Once again, your classification as a secretor is determined by your biology and there isn’t anything you can do to put yourself in the non-secretor category.
  • Blood type – depending on the type of blood you have, you secrete different scents. Studies have shown that mosquitoes are most attracted to Type O blood and least attracted to Type A.
  • Lactic acid – lactic acid is emitted through your skin when you are active or eating certain foods. Mosquitoes are more attracted to people with a greater build-up of lactic acid on their skin. You can reduce lactic acid by washing with soap after exercising and thoroughly drying.

There are also other indicators like body heat, moisture, movement and color that attract mosquitoes’ highly attuned receptors.

Additionally, drinking a cold beer on a hot day may lead to more bites.

A separate study of men who drank either beer or water revealed that “beer consumption” consistently increased mosquitoes attention.

Now for some good news.

Since human scent is the primary indicator for mosquitoes to target certain people, it's easy to mask your personal scent with an insect repellent.

Which means, your scented friend next to you may become the mosquitoes prime target.

You can easily find an insect repellent that’s right for you by using this EPA’s search tool.

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