Mosquito Magnet? It depends on the mosquito

There is nothing better than a summer-dusk outdoor meal with friends, especially friends who act as mosquito magnets, attracting all the attention and leaving me to enjoy some ribs, a pinot, and conversation free of bites. 

How Mosquitoes Find the Buffet

For a long time, mosquito science on “why us” focused on the carbon dioxide we exhale. It notifies the mosquito of a potential snack and provides an approximate location where it can be found. As one study notes,

“Carbon dioxide (CO₂), emitted by all potential blood hosts, is a key kairomone for mosquitoes, which signifies the presence of a blood source and sensitizes them to other host sensory cues.”

Our exhaled CO₂ forms a shifting plume that mosquitoes can detect and follow, zigzagging through the air as they close in. The gas effectively triggers host-seeking behavior, heightening their responsiveness to visual cues, body heat, and skin odors. Some of those odors act as kairomones—chemical signals that inadvertently benefit another species. In this case, we send the signal, and the mosquito cashes in.

Having arrived at the human buffet of my summer soiree, how do mosquitoes decide which specific individual to dine upon? A new study offers an intriguing answer: what makes one person irresistible may depend on which mosquito is doing the choosing.

Not Everyone Smells the Same to a Mosquito

Much of what mosquitoes smell does not come directly from our skin. Skin secretions that begin with little or no odor are transformed by our skin-residing microbes into airborne volatile organic compounds, or VOCs. Humans give off more than 1,000 of these compounds, creating a formidable chemical haystack in which researchers must search for molecules that attract, or, dare we hope, repel mosquitoes.

In one corner, there were 119 volunteers who participated in the study and were asked to arrive without having showered and to avoid applying skin products and fragrances. In the other, three mosquito species. Aedes aegypti and Aedes albopictus, spreaders of dengue, Zika, and an OG of mosquito-borne illness, yellow fever; and Culex quinquefasciatus, a transmitter of West Nile virus. 

Researchers measured attraction by placing participants’ arms in a controlled wind tunnel supplied with carbon dioxide and counting how many mosquitoes flew toward each person’s scent. They also captured and chemically analyzed the airborne odor molecules and swabbed participants’ skin to characterize the bacterial communities associated with those distinctive odors.

The first surprise was that there was no universal “mosquito magnet.” An individual highly attractive to one mosquito species was often ignored by another. Our familiar claim that someone is simply “the one mosquitoes always bite” may be missing half the story: attraction depends not just on the person, but on the mosquito.

• Distinct Chemical Profiles: Analysis of airborne skin chemicals, the VOCs, revealed clear sex-based differences. However, while Aedes aegypti showed a slight preference for male over female skin, the other two species were skin “agnostic.” 
• Chemical Push vs. Pull: Attraction was not simply a matter of smelling more delicious. For Aedes aegypti, differences among people appeared to be shaped largely by compounds that deterred the mosquito—a chemical “push.” Aedes albopictus, by contrast, appeared more responsive to compounds that pulled it toward particular hosts.
• Universal Microbial Beacons: Although human skin microbiomes vary widely, only one bacterial species was shared among all participants. Some fellow travelers were consistently present in every highly attractive participant, suggesting that these microbes produce universal olfactory signals that attract blood-feeding insects.

The chemistry of mosquito preference might seem like backyard trivia, until you find that your insect dining companion brings along some unwelcomed +1s. 

From Backyard Nuisance to Public Health Problem

In much of the United States, a mosquito bite is still experienced primarily as a summertime nuisance. Elsewhere in the Americas, the stakes can be much higher. As temperatures warm, trade expands, and urbanization increases, these three “bad actors” are moving to higher latitudes and altitudes. For example, Aedes aegypti, responsible for the majority of the hemisphere’s mosquito-borne illness, resulted in over 1.4 million cases of Dengue fever in 2025. In severe instances, this leads to hemorrhagic death. Aedes albopictus, responsible for Dengue, Zika, and Chikungunya, already has an established range in the Eastern and Southeastern US. Culex quinquefasciatus is responsible for the most mosquito-borne illness in the US, West Nile Virus. As some of these mosquitoes expand into new territory, understanding whom they seek out becomes more than a matter of avoiding an itchy evening outdoors.

Public-health efforts to reduce mosquito-borne disease have traditionally relied on measures ranging from eliminating breeding sites and using insecticides to personal protection. More recently, researchers have also tested genetic approaches designed to suppress populations of disease-carrying mosquitoes. One such genetic alteration, lethal to embryonic female mosquitoes, was shown to reduce wild populations of Aedes aegypti by 95%. However, fear of releasing “mutant bugs” that could cause permanent ecological disruption or collapse has slowed public acceptance.

Could we instead change the chemical signals we send?

Could We Change the Signal?

One possibility—still speculative—would be to alter the skin microbiome itself. In principle, benign bacteria might someday be used to crowd out microbes associated with mosquito-attracting odors or to change the VOCs our skin releases, making us harder for mosquitoes to find or less appealing once found. Such an approach would face substantial hurdles: the skin microbiome resists change, sweating could make any topical treatment short-lived, and repeated application might test even the most diligent user's commitment. [1]

Another possibility may be easier to imagine: baiting mosquito traps with microbially generated scents tailored to the species circulating in a particular region. Farther down the road, researchers might even identify people who are especially attractive to medically important mosquitoes and develop a lotion or potion that alters the signals their skin sends. That would give new meaning to personal protection. 

And at my next summer dinner, instead of choosing my seat away from the friend mosquitoes love most, perhaps we'll all have a fighting chance at finishing the ribs unbitten.

[1] This approach is not without its inherent difficulties, including the skin microbiome’s general resistance to change and our usual sweating, which would require applying a “probiotic microbial strain” like sunscreen, often and in large measure. And we do not know how introducing new members to the microbiome might disrupt the skin’s barrier function or cause inflammation (dermatitis).

Source: Individual humans are more attractive to certain mosquito species iScience DOI: /10.1016/j.isci.2026.117006