Researcher New substance can protect against mosquitoes

Find researchers „chemical cloak of invisibility“ against mosquito bites

06/12/2013

Mosquitoes identify their food sources via olfactory cells, which can sense both human skin and exhaled carbon dioxide. The currently available anti-mosquito funds therefore help only very limited against mosquito bites and transmitted by them diseases such as malaria or dengue fever. However, US researchers have recently made a breakthrough in the development of a mosquito remedy. They found flavors that block mosquito olfactory cells. Their results are presented by the scientists in the journal „Cell“ in front.

To protect against mosquitoes, olfactory cells of the animals are blocked
If it is possible to block the olfactory cells of mosquitoes, humans are no longer perceptible to them as a source of food. Genevieve Tauxe and her colleagues at the University of California at Riverside took advantage of this by looking for a flavoring that eliminates the animal's olfactory cells. To do this, the researchers studied more than 440,000 substances, some of them as „chemical cloak of invisibility“ could be suitable. They tested the flavors of the two mosquito species Anopheles gambiae, which transmits malaria, and Aedes aegypti, which delivers the viruses of dengue and yellow fever to their host.

Earlier research had already shown that Mosquito's carbon dioxide is detected by so-called cpA neurons. Tauxe and her team have now discovered that other fragrances of the human skin can be identified by animals via these olfactory receptor cells. „We have found that the CO2-sensitive olfactory cells of Aedes aegypti and Anopheles gambiae are also a sensitive detector of the odors of human skin. We show that the activity of these neurons is important for the attraction of the skin odor and that they are the central target for intervention“, the researchers write in the journal.

Various flavors protect against mosquitoes or attract them
The researchers discovered various substances, some of which blocked the mosquito's olfactory cells and others activated them. For example, ethyl pyruvate eliminates the re-spores, so that the substance - applied to the skin - causes mosquitoes can no longer perceive the skin odor. As the researchers report, the flavoring agent has a pleasant odor. On the other hand, cyclopentanone activates the olfactory cells, so that the substance can be used to attract the animals for mosquito traps.

„Our analysis provides very realistic opportunities to use simple, natural, cheap and pleasant flavors to keep mosquitoes from finding people, "explains study leader Anandasankar Ray „Cell Press ".

The researchers' findings could help curb the spread of malaria, dengue fever and other mosquito-borne diseases. This would benefit mainly Asia and Africa, where the diseases are widespread. According to the World Health Organization (WHO), around 220 million people worldwide suffered from malaria in 2010, and around 660,000 died as a result of the disease. (Ag)