Mosquitos are vectors for diseases such as malaria, dengue and West Nile virus. However other insects such as horse flies, deerflies, Tsetses flies may also serve as viral vectors. This issue is more prevalent in the developing world, where poor access to healthcare leads to rapid transmission and spread of insect-borne pathogens. Studies have shown that insects detect humans through the CO2 that they exhale rather than their skin odor. Traditional insect repellants such as DEET have low volatility and need to be applied on to the skin or to garments at high concentrations to remain effective.
Prof. Anandasankar Ray and his colleagues at the University of California, Riverside (UCR) have developed insect repellants to deter insects from detecting and biting humans. The repellants are comprised of a group of compounds consisting of an aldehyde, mono- or diketone and an alcohol. Repellants mask the insect’s ability to detect CO2. These repellants can be delivered in a variety of forms and can be used in much smaller concentrations and remain effective for much longer when compared to traditional repellants like DEET.
The UCR lab also developed and patented a computational assay to screen and identify mosquito repellents. This assay was used to identify the patented compounds that disrupt CO2 sensing in mosquitos.
Fig. 1 Effect of inhibitory odor, 1-hexanol, on mosquito neuronal CO2 response. The small black bar indicates an 0.5 second exposure to inhibitory odor overlayed with a 3 second response to CO2. The second chart shows how CO2 response is mitigated by the odor
Fig. 2 Effect of pre-exposure to inhibitory odors on long-term reduction to CO2 response. The response to a 0.3% CO2 impulse over 6 minutes was measured every 30 seconds after an initial 3-second exposure to an ‘odor’ mixture (black bars). The odor mixture consisted of 1-hexanolo, pentanal, butanal, and 2,3-butanedione at 10-2 concentration. Paraffin oil (white bars) was used as a control
|United States Of America||Issued Patent||9,523,675||12/20/2016||2009-334|
|United States Of America||Issued Patent||8,945,595||02/03/2015||2009-334|