Have you ever noticed that you get bitten more by mosquitoes than the people around you seem to? Or do you know someone that always seems to have mosquitoes following them around? In this article, we will be breaking down some of the reasons mosquitoes are attracted to humans, as well as a brief review of new research on mosquito attraction published last fall.
The term “mosquito magnet” refers to individuals who appear highly attractive to mosquitoes. In the US, ~20% of individuals report that they believe they are mosquito magnets, meaning one in five people are in dire need of Mosquito Squad’s treatments to protect them this season. But are “mosquito magnets” backed at all by science? Or is this a case of confirmation bias? To answer these questions, we first have to understand how mosquitoes find human hosts and whether or not there are certain attractants that influence host finding.
What do mosquitoes look for when host finding?
Like most insects, mosquitoes have compound eyes comprised of thousands of lenses. This leaves mosquitoes with poor eyesight, only able to perceive the world through a blur of shapes and colors. In order to find a host for a bloodmeal, mosquitoes use a combination of senses and environmental cues to identify and track a nearby host.
Attractants in your control:
There are several things you can do to make yourself less of an easy target for mosquitoes:
- Colors: Darker, more saturated colors attract mosquitoes.
- Lights: Mosquitoes use daytime and nighttime cues to determine good times to host find.
- Skin Odors: Fragrant perfumes, deodorants, and body sprays may attract mosquitoes (and other insects).
- CO2: Carbon dioxide stimulates other senses mosquitoes have, and the more you breath, the easier it becomes for them to detect and find you.
Attractants out of your control:
- Skin Volatiles: Chemicals and molecules naturally produced by microbiota on the skin (think skin oils, pores, hair follicles, and other bacteria present along the skin).
Sulcatone is a prime example of skin volatiles and mosquito attractant out of your control. This chemical is present at unique levels in humans relative to other animals, and some mosquitoes (like Aedes aegypti) have developed special receptors to pick up on sulcatone scents. Though you can wear an insect repellent or bug spray to discourage mosquitoes from visiting you, there is little you can do to convince mosquitoes that you are not a human host.
A New Discovery!
In October 2022, a new paper was published in the journal Cell explaining a new reason for mosquito magnetism: carboxylic acid levels on your skin. During a 3-year research study, scientists in New York identified highly attractive and lowly attractive individuals using a two-choice olfactory assay. In this set up, the researchers tracked how many mosquitoes preferred one participant over another, and after analyzing the skin microbiota for each participant, it was found that highly attractive individuals have more carboxylic acids present in their skin.
So… what does this mean for Mosquito Magnets?
This research provided us with two important things. First, it seems to confirm that some individuals are innately more attractive to mosquitoes than others, proving that mosquito magnets DO exist! Second, this unlocks a new realm for further mosquito control and management research. Now that we understand skin volatiles play important roles in mosquito attraction, new bug sprays and repellents may be developed with these less detectable skin odors in mind.
If you want to learn more about this research, click the link below to access the full paper for free: