Mosquitoes being more attracted to some people than others is an observed phenomenon but one that is poorly understood, the research to be published in the scientific journal Cell notes.

Researchers from The Rockefeller University, a New York-based postgraduate research institution, identified carboxylic acids on the skin as an attractant that could lure mosquitoes.

People with significantly higher levels of the acids were more attractive to mosquitoes.

Even mutant mosquitoes without the receptors to smell the acids were still more attracted to those with higher acid levels on their skin.

“This suggests that mosquitoes with significant olfactory deficits are still able to tell the difference between individual people,” the research notes.

Attractiveness can vary wildly.

The researchers determined an “attraction score” based on how mosquitoes flocked to their subjects, finding the most attractive person for the mosquitoes scored four times higher than the second most.

Compared to the least attractive, their score was 100 times higher.

The researchers believe their findings provide more scientific reasoning for the phenomenon of mosquito attraction than existing theories based on blood type, or the consumption of B vitamins or garlic as a home repellent.

However, uncertainties remain.

The specific chemical mechanism that differentiates the attractiveness of people to mosquitoes is still unclear, the research notes, while the consistency of skin odour over time is also unknown, particularly “the markedly less intense skin odour that emanates from body sites commonly bitten by mosquitoes”.

The research could inform the development of more effective insect repellents.