How Mosquitoes 'Smell' Human Prey

It may be winter in the North, but mosquitoes are still very much a nuisance south of the equator. Now researchers are investigating how exactly these disease-carrying pests home in on humans in the hopes of finding a way to make us essentially invisible to the bloodsuckers.

Nature World News has previously reported about how experts are experimenting with various ways to fight the spread of mosquito borne diseases, such as Dengue fever or the dangerous West Nile virus.

These strategies often have to do with the mosquitoes themselves, either controlling their population numbers or modifying how their bodies react to the presence of a virus. However, if scientists could simply take humans off the mosquito menu, researchers would no longer have to tamper with nature so directly.

"What's emerging... is a picture of exactly how mosquitoes are navigating their environment to locate humans, and in the end, we may able to use that knowledge to fine-tune a line of attack that distracts their preference for humans altogether," researcher Felix Baier, at Harvard, explained in a statement.

Baier helped author a study recently published in the journal Nature, which details how a key genetic variation in female (bloodsucking) mosquitoes helps the insects "smell" humans.

According to the study, humans regularly emit a compound called sulcatone. Various expressions of the gene Or4 encode for receptors in a mosquito's antennae cells that detect this compound, urging the pests towards humans.

"Humans emit it much more than any of the other animals we tested," Baier said. "And that makes sense - it's something a mosquito could use to distinguish between human and other mammals."

According to Baier and his colleagues, there may be a way to hide human sulcatone from mosquitoes. "Blinding" mosquitoes to the compound directly, such as by attacking the development of their sulcatone receptors, is one such idea.

Obviously, Baier adds, doing that won't be easy.