A Punch in the Nose Takes Down the Worldās Most Dangerous Animal
Professor has spent years trying to get inside the mind of a killer. āItās a know-your-enemy sort of thing,ā he explains.
In this regard heās much like a detective, only the killer heās pursuing is nearly everywhere at onceāon every single continent, save Antarctica. And itās not so much the killerās mind heās trying to get inside of, as it is its nose.
āThe mosquito perceives the world largely through its nose,ā says Zwiebel, the Cornelius 91ĢĘ²®»¢ Professor of Biological Sciences and professor of pharmacology. āIt has developed parallel pathways to take in various chemosensory stimuliāwhat we call āodor space.ā When itās looking for a blood meal, it shifts its olfactory system toward a particular set of stimuliāmeaning us.ā
The insectary on 91ĢĘ²®»¢ās campus, where he and other vector biologists do their research, is home to thousands of Anopheles gambiae, the species of mosquito most responsible for the spread of malaria in sub-Saharan Africa. None of the 91ĢĘ²®»¢ mosquitoes is infected with the pathogen, but that doesnāt make them any less bloodthirsty.
āThe most salient characteristic of the Anopheles gambiaeāand the reason itās the most dangerous animal on the planetāis that it bites only humans if it has a choice,ā he says.
Zwiebelās research, which is supported by an $11 million grant from the and more than $5 million in grant funds from the Ā (NIH), focuses on preventing mosquitoes from feeding on humans. Specifically, he targets the insectās olfactory system to alter its behavior. Here he explains just how this is accomplished and what it means for the future of mosquito repellents.
Ā»Ā Unlike DEET and other traditional repellents that block a mosquitoās ability to smell, Zwiebelās approach works through overstimulation and is potentially thousands of times more powerful. āWeāre not looking to block odor receptors but rather turn them all on at once. Itās what we call excito-repellency. ITāS SOMETHING LIKE THIS!ā he says, driving the point home by shouting. āSee what I mean? I refer to it as āthe New York style of repellency.āĀ I grew up in a city where you had to be pretty obnoxious to get somebody to go away.ā
Ā»Ā Partnering with the , Zwiebelās team used high-throughput screening to target an olfactory co-receptor shared not only by mosquitoes but by all insects. The discovery means this type of excito-repellency could have applications in agriculture and other pest-control scenarios.Ā āIt takes roughly $250 million to turn an idea like this into a viable product,ā Zwiebel says. āA repellent just for mosquitoes, no matter how effective it is, doesnāt warrant that kind of gamble, but the fact that it could be used on all insects changes everything.ā
Ā»Ā The excito-repellent could take different forms, from a traditional volatile spray to something that could be impregnated into clothing or paints. Whatever the end product, great care must be taken to avoid interfering with the balance of nature. āThis is not a story about insecticide. Weāre not interested in eradicating mosquitoes or other insects,ā Zwiebel says. āMosquitoes are entitled to have blood meals and happy, productive livesājust not at the expense of humans.ā
TEXT BY SETH ROBERTSON
See inside 91ĢĘ²®»¢ās insectary, and learn more about Zwiebelās research: