Overview

Researchers have found that people who are most attractive to mosquitoes produce a high concentration of chemicals on their skin that is tied to smell. And if you’re one of those people, bad news: these pesky insects are devoted to their favorite foods and will feed on them repeatedly.

The science and other stuff to know

To find out why some people seem to smell better to mosquitoes than others, researchers at Rockefeller University in New York decided to put mosquito magnetism to the test. They designed an experiment pitting people’s scents against each other. The team then asked 64 volunteers to wear nylon stockings around their forearms to pick up their skin smells.

Afterward, they cut the stockings into two-inch pieces and placed the fabric behind two separate trap doors in a clear plastic box. They then released dozens of mosquitos to fly to the bait — the stockings — behind the first or the second door. The team then held a round-robin tournament and ended up with a surprising discovery. One of the samples, described as being from “subject 33,” emerged as a favorite of the insects. As per the study, published in the journal Cell, “subject 33” had high levels of compounds called carboxylic acids. And people with similar acids on their skin are more likely to be “mosquito magnets,” the study concluded.

This means that if you have high levels of this substance on your skin, you’ll be the one being bitten all the time when you go outdoors.

The experiment used the Aedes aegypti mosquito that spreads diseases like yellow fever, Zika, and dengue. Vosshall said she’d expect similar results from other kinds, but would need more research to confirm. In addition, the study didn’t answer why some people have more carboxylic acids on their skin than others. But Vosshall said the composition of the skin microbiome is unique in every individual.

So what?

While you can’t get rid of skin acids or smells, the findings could help find new methods to repel mosquitoes. It could also lead to new products that could mask or alter certain human odors. This can make it harder for mosquitoes to find human blood and potentially curb the spread of diseases.

Still, figuring out ways to fight off mosquitoes isn’t easy, said Jeff Riffell, a neurobiologist at the University of Washington who wasn’t involved with the study. Riffell explained that these insects have evolved to be “lean, mean-biting machines.”

“Mosquitoes are resilient,” Vosshall said. “They have many backup plans to be able to find us and bite us.”

What next?

Experts have long known mosquitoes have a preference for some humans over others. For instance, people tend to become more attractive to mosquitoes when they’re pregnant. Or if they’ve had a few beers. To solve mosquito bite problems, scientists have come up with innovative ways to fight these insects, such as this 3D-printed wearable ring that repels mosquitos.