Quantifying Aedes aegypti Host Odor Preference Using a Two-Port Olfactometer

Area of Science:

• Entomology
• Neuroscience
• Public Health

Background:

• Blood-feeding mosquitoes transmit diseases like Zika, dengue, and malaria, posing a significant global health risk.
• Mosquitoes use visual, thermal, and chemical cues to locate hosts for blood meals.
• Understanding mosquito host-seeking behavior is crucial for developing effective vector control strategies.

Purpose of the Study:

• To describe a novel assay for quantifying odor-based host-preference behavior in mosquitoes.
• To replicate medium- to short-range host-seeking behaviors relevant to host landing.
• To assess the reliability of relative mosquito response versus absolute counts in two-choice tests.

Main Methods:

• An assay was developed to measure the preferential approach of mosquitoes toward different odor sources.
• The assay accommodates various odor sources, including live animals, animal breath, and CO2-scented sleeves.
• Mosquitoes navigate upwind to an odor source within 30 cm and are then collected in a trap.

Main Results:

• The assay effectively measures odor-based host-preference behavior in mosquitoes.
• Relative mosquito response in two-choice tests demonstrated lower trial-to-trial variation compared to absolute response counts.
• Absolute mosquito response was found to be sensitive to external factors like rearing conditions.

Conclusions:

• The developed assay provides a reliable method for studying mosquito host-seeking decisions.
• This research offers fundamental insights into mosquito neurobiology and behavior.
• The assay can aid in designing innovative strategies for mosquito-borne disease control.