But why do mosquitoes bite some people and not others?

 

There is no such thing as "mosquito skin". But it turns out that several factors do attract mosquitoes.

 

Have you ever wondered how unfairly you are always the one who gets eaten by mosquitoes while others around you still come out unscathed? Know that "mosquito skin" does not exist. However, various studies have found different factors that whet mosquitoes' appetite. Here are which ones:

 

CO2 production

According to some studies, mosquitoes are able to spot the release of CO2 up to 50 meters away. And they happen to have a marked preference for those who produce the most, which makes overweight people particularly popular targets, but not only that. Pregnant women also produce 21% more CO2 than others and are therefore particularly attractive to mosquitoes.
If the release of CO2 is the first reason that attracts a mosquito to its prey, it will then refine its selection according to other criteria.

Body odor

These dreaded insects are also much more sensitive to scents than we are, although the attraction to a particular scent depends on the species. Thus, Aedes gambiae prefers, for example, the odors given off by our hands and feet. And mosquitoes tend to be attracted to the smell of sweat because it gives off substances that attract them, such as lactic acid.

 

But why does our body odor differ from one person to another so much that mosquitoes don't bite us all equally?

The genetic factor

Various studies have proven that our body odor has a genetic basis. For example, the authors of a study published in PLOS One confronted twins with mosquitoes of the Aedes aegypti species. "And, as might be expected, identical twins with all of their genes in common consistently had more similar scores than fraternal twins thus highlighting an obvious genetic component," says an article by The Conversation published in 2018. "According to this comparison, 67% of the differences between people are due to their genes."

 

Bottom line, part of the reason you attract mosquitoes is your genes. Difficult to fight against ...

Bacteria specific to each person

But that's not all. At the origin of these unique scents, we also find the bacteria of the skin. You should know that we only share a small fraction of microbial species with each other. For the rest, our microbial footprint is specific. And we don't choose it. As researcher Tim Spector explains, "just like mosquitoes, if some microbes prefer to coexist with us, others will settle elsewhere."

 

However, Dutch researchers published a study in 2017 in which they claim that certain bacterial compositions are more likely to attract mosquitoes than others. For example, they discovered that the species Anopheles gambiae develops a preference for people whose skin carries a significant amount of bacteria and whose species diversity is lower than that of the most spared individuals.

 

A preference for dark colors

More anecdotally, once near its prey, the mosquito would tend to prefer dark colors, according to James Day, a medical entomologist at the University of Florida. In a 2017 BBC interview, he explained that people who wear black, dark blue or red are more likely to get stung.
 
Note, however, that the visual factor only comes into play when the mosquito is less than 1.50m from its prey. Moral, as a last bulwark, prefer light colors.