Why Mosquitoes May Prefer Some People

Originally published 2016-04-14.

A mix of factors, not a personal defect

The article discusses possible influences on attraction. No single trait in the list establishes why one person was bitten on a particular evening.

You may have heard the explanation that mosquito ‘victims’ have sweeter blood, but this is not the case. Rather, it is the fact that people vary in the types of bacteria that exist on their skin, and some bacteria emit better smells than others, which determine whether the mosquitoes want a taste!

In addition to differing bacteria, carbon dioxide given off in our breath, the heat of our bodies, and some other surprising factors make those who are bitten frequently, quite irresistible. Unfortunately, there is more at stake than itchy bumps, and the following video that goes into greater detail about risks and protection, is a must-see.

As mosquitoes carry many potentially life-threatening diseases, making good choices concerning repellents, is extremely important. Mosquito bites aren't just an annoyance; given the health risks, this footage is an introduction, not a guarantee of protection or a substitute for current local guidance.

What a 2022 study found

In a study published in Cell in October 2022, researchers at Rockefeller University led by Maria Elena De Obaldia and Leslie Vosshall asked 64 volunteers to wear nylon sleeves on their arms for six hours, then tested how strongly the samples attracted Aedes aegypti, the mosquito that spreads dengue, yellow fever and Zika. Attractiveness varied widely: the most attractive person’s samples were four times as enticing as the next most attractive and more than 100 times as enticing as the two least attractive. Carboxylic acids, a type of fatty acid, were heavily enriched on the skin of the most attractive volunteers, and their levels stayed stable for a year or more; De Obaldia called the trait “a very stable property of the person”. The study showed an association rather than a cause, and one volunteer with high levels of all the acids examined did not attract mosquitoes.

Sources: NIH Research Matters, 1 November 2022: Skin compounds associated with attractiveness to mosquitoes

Source: Why Don't You Try This

Attraction and disease risk are separate questions

Mosquito attraction involves several cues rather than a single personal trait. Being bitten more often does not by itself identify the mosquito species or the infection risk in a location. The video cannot guarantee a safer summer; protective choices need current local guidance and appropriate product instructions.