After initial research, which produced a more complete understanding of how mosquitoes are attracted to human skin, they then identified compounds which might inhibit or amplify this.
From the UCR news release:
Next, using a chemical computational method they developed, the researchers screened nearly half a million compounds and identified thousands of predicted ligands. They then short-listed 138 compounds based on desirable characteristics such as smell, safety, cost and whether these occurred naturally. Several compounds either inhibited or activated cpA neurons of which nearly 85 percent were already approved for use as flavor, fragrance or cosmetic agents. Better still, several were pleasant-smelling, such as minty, raspberry, chocolate, etc., increasing their value for practical use in mosquito control.
Confident that they were on the right track, the researchers then zeroed in on two compounds: ethyl pyruvate, a fruity-scented cpA inhibitor approved as a flavor agent in food; and cyclopentanone, a minty-smelling cpA activator approved as a flavor and fragrance agent. By inhibiting the cpA neuron, ethyl pyruvate was found in their experiments to substantially reduce the mosquito’s attraction towards a human arm. By activating the cpA neuron, cyclopentanone served as a powerful lure, like CO2, attracting mosquitoes to a trap.
I find this pretty intrigueing. I wonder if something might become available in time for next year's bug season?
I originally found this story in this scienceworldreport.com article.