Human attractiveness to Aedes albopictus : sweat amino acid associations and functional screening of skin volatiles

BACKGROUND: Human-derived chemical cues are central to mosquito host-seeking and may provide candidates for odor-baited surveillance and attract-and-kill tools. However, the factors associated with inter-individual attractiveness to Aedes albopictus (Skuse) and the behavioral activity of corresponding skin volatiles remain incompletely characterized. RESULTS: metrics were not significantly associated with attraction. In a subset of nine volunteers, total sweat amino acid concentration was inversely associated with attraction (r = -0.812, P = 0.008). Headspace solid-phase microextraction gas chromatography-mass spectrometry detected 28 skin volatiles, including 5 compounds present in all volunteers and 10 volunteer-specific compounds selected with the common compounds for functional screening. Electroantennography showed significantly greater responses to all five common compounds than to liquid paraffin and to crotonaldehyde than to n-hexane. Dual-choice bioassays identified six compounds with positive directional responses after Holm-Bonferroni correction: decanal, nonanal, tricyclodecenyl acetate, tetradecanol, tridecane and (E)-2-dodecen-1-ol. CONCLUSION: The integrated chemical, electrophysiological and behavioral workflow identified an inverse association between sweat amino acid concentration and human attractiveness, and defined six skin volatiles as priorities for dose-response, blend and semi-field evaluation toward Aedes albopictus lure development.