In a joint effort reported in the Jan. 15 issue of the journal Nature, researchers at Vanderbilt and Yale universities have verified that the antennae of female Anopheles mosquitoes that prey on humans contain receptors that respond to one of the chemical compounds found in human sweat.
"This validates our hypothesis that the olfactory system of mosquitoes--and other insects--consists of an array of different receptors, each of which responds to a very narrow range of odorants," says Laurence J. Zwiebel, associate professor of biological sciences at Vanderbilt, who participated in the study. His co-authors were Vanderbilt graduate student A. Nicole Fox along with Yale colleagues Elissa A. Halem, a graduate student, and professor John R. Carlson.
Confirmation of this hypothesis means that it should be possible to identify the specific human odorants and the protein receptors that allow female mosquitoes to identify their hosts when they need blood to satisfy their reproductive needs. In addition to cataloging the human odorants that attract mosquitoes, it also will allow the researchers to go further and search for additional chemicals that either attract or repel these highly selective insects.
"Looking at attractants is only half of the picture. There is no evidence that mosquitoes find some human odorants repellent, but we're interested in exploring this," says Zwiebel. Such discoveries might lead to new and more effective repellants that could play a major role in reducing the death toll from diseases spread by mosquitoes, including malaria, encephalitis, West Nile, dengue, hemorrhagic and yellow fevers.