Mosquitoes
No, it's not just an impression. There are people who are really targeted by mosquitoes, much more than others. There was already scientific evidence, but the reasons remain unclear. According to a new study by Rockefeller University in New York, just published in the journal Cell, however, it depends (also) on the fact that the "mosquito magnets" give off an inviting scent: a mix of chemicals that makes insects come to mouth watering and that baths and cosmetics cannot completely erase. Here's what it is and how the discovery could be used to our advantage.Magnet for mosquitoes
Scientists have long known that mosquitoes have preferences for some humans over others: pregnant women, for example, or anyone after drinking beer. Clues that seem to indicate that even the smell of a person contributes to attracting annoying and sometimes dangerous insects. However, the molecular reasons for this phenomenon are still not entirely clear.To try to shed some light on this mystery, Leslie Vosshall and her team for three years have collected the natural smell of dozens of volunteers by putting on their nylons on their arms. The socks impregnated with the odor of the participants were then proposed to the mosquitoes of the Aedes aegypti species (the one that can transmit diseases such as Zika and Dengue), in a sort of two-way fight, the winner of which was the champion most liked by insects. In this way, the researchers identified the most delicious smells and were able to analyze them.
They found that these samples contained higher levels of compounds called carboxylic acids, molecules that are normally found on our skin, produced from our cells and the skin microbiota. Some of these, if present in excess, are responsible for the typical smell of feet or cheese.
Confirming that carboxylic acids are at least partly responsible for the preference of mosquitoes for certain people and not for others, there is the fact that mutant mosquitoes for the receptor of these compounds have been shown not to have a marked preference like their unmodified counterparts.
No remedy, yet
The US team has discovered something else as well. In three years of experiments, the ranking of approval of the samples has not changed. In other words, as Vosshall summed up, "if you are a mosquito magnet today, you will be a mosquito magnet even in three years' time."Research has not yet investigated why some people have higher levels of carboxylic acids on the skin than others. Continuing to study, however, there is the possibility of understanding whether changing certain habits involves a change in the chemical profile of our odor, but also of finding products to manipulate it, perhaps a probiotic cream that reduces the production of these compounds so attractive for the mosquitoes. We await the developments.