Mosquitoes Have Their Own Tastes: Why Some Folks Get Bit More Than Others

If you’ve ever swatted at a buzzing nuisance and wondered why your friend seemed to be the mosquito’s favorite snack, you’re not alone. It turns out that these tiny insects are surprisingly selective diners – they don’t just bite anyone who wanders past.

In our lab at the University of Miami, a team of biologists set out to crack the mystery. We focused on three species that dominate South Florida’s air: the urban‑loving Aedes aegypti, the adventurous Asian tiger mosquito Aedes albopictus, and the bird‑preferring southern house mosquito Culex quinquefasciatus. Each of them carries its own cocktail of diseases, from Zika and dengue to West Nile virus.

To keep things humane (and to avoid any unwanted welts), we recruited 119 volunteers and asked them to sit still while we observed the mosquitoes’ choices in a device called a uniport olfactometer. Think of it as a three‑part acrylic tunnel: a box for the participant’s arm, a release tube for the insects, and a tiny “attraction chamber” where the bugs could drift in but not bite. For each trial we let 30 mosquitoes of a given species wander toward the arm, counted how many slipped into the chamber, and repeated the test three times per species. That added up to 270 insects per participant.

But we didn’t stop at counting flies. Right after each trial we swabbed the participant’s arm and collected the surrounding air in a sealed bag. Those samples let us profile the skin’s microbiome – the community of bacteria that lives on us – and sniff out the volatile compounds wafting off the skin.

The results were messy, in a good way. All three mosquito species showed clear preferences, but each was attracted by a different blend of smells and microbes. Aedes aegypti seemed to favor men just a smidge more than women, although we couldn’t pin down a single scent that explained the difference. What we did notice was that participants with lower levels of certain cyclic alcohols (common in perfumes) were more attractive, while higher numbers of Staphylococcus bacteria correlated with more bites. Conversely, an abundance of Pseudomonas appeared to deter them.

Aedes albopictus was the least picky of the trio. It gravitated toward people whose skin emitted plenty of ketones – especially mesityl oxide, which smells oddly sweet, like honey. This species also liked arms teeming with diverse microbes, particularly Streptococcus intermedius and Anaerococcus octavius. Interestingly, it steered clear of volunteers who carried a lot of Mogibacterium, suggesting that some bacteria may produce repellant odors.

Meanwhile, Culex quinquefasciatus behaved a bit like a mixed bag. It didn’t care much about the host’s sex, but it showed a strong affinity for participants with higher levels of certain fatty acids and lower counts of the bacterium Cutibacterium acnes. Those who had more of the latter seemed to get fewer bites.

What does all this mean for the average person? For one, the perfume you reach for every morning could actually be sending mixed signals to hungry mosquitoes. Skipping heavy fragrance, especially those with cyclic alcohols, might make you less appealing to Aedes species. On the other hand, maintaining a healthy, balanced skin microbiome – something we normally think of as a good thing – might inadvertently draw in more insects.

Understanding these nuances opens the door to new, more targeted repellents. Imagine a skin probiotic that encourages growth of bacteria mosquitoes hate, or a scented lotion that masks the attractive ketones. That’s the longer‑term vision: to turn the tables on these picky eaters rather than just swatting them away.

Of course, we’re still early in the research, and individual variations are huge. Still, the takeaway is simple: mosquitoes are choosy, and the tiny ecosystem living on our skin plays a starring role in the drama.