Scientists Try to Design a Safer Mosquito

When it comes to style and form, nature may be the most elegant designer out there. Still, though, in the race for human lives, at least one U.S. and British team of scientists is out to beat her at her own game.

Over the past two weeks, the global health world has seen an unusual rash of headlines on new ways to kill mosquitoes (the prime vehicles of certain diseases), each successively more futuristic than the last.

First, there was the debut of a Death Star-like laser that could shoot down up to 100 flying mosquitoes per second -- as memorably introduced onstage at the latest TED ("Ideas Worth Spreading") conference in California.

And now, scientists are announcing that through genetic engineering, they may have found a way to stop a certain kind of mosquitoes, Aedes aegypti, from flying at all.

Currently, there's no such thing as treatment or a vaccine for the dengue virus, which experts say affects up to 100 million people a year and threatens over a third of the world's population, mostly in Africa and southeast Asia. But by breeding female mosquitoes with stunted wing growth (only females bite and transmit disease), scientists estimate they could put a halt to the virus's spread within six to nine months. To do so would require distributing thousands of eggs, which in turn would produce a new generation of "grounded" female mosquitoes.

Unlike the killer laser machine (can't believe I'm using this phrase in a serious post), which is calibrated to zap anything that hums at a mosquito's wing frequency, this genetic modification applies only to the mosquitoes that spread dengue fever.

There's actually a surprisingly robust history of people tinkering with mosquito genetics to try and guard against the spread of disease. Certainly, there's some cautionary tales: Back in 2000, when an early batch of GM mosquitoes were created, they proved less hardy than their wild counterparts -- too weak to last long outdoors.

Still, though, that hasn't stopped others from continuing to experiment. One Arizona professor has tried to shorten the lifespan of mosquitoes -- even by just one day -- so that they won't have time to develop and transmit diseases to humans. Another researcher at John Hopkins University developed a mosquito with a protein that could block malaria infection. Yet another researcher has taken a still more unusual tack, creating a GM mosquito population offering males that boast fluorescent testicles, allowing them to be easily recognized and sterilized. (The idea is that large numbers of sterile males could be introduced into the wild to mate with normal females, thereby bringing the number of malaria-carrying mosquitoes down.)

Genetic modification tends to send reflexive chills down many people's backs. But scientists involved argue that by reducing the need for aggressive use of insecticides, their interventions are cleaner and more environmentally sound.

In either case, the proof is in disease-communication rates. In which case, however promising the latest round of news sounds, we've still got awhile to anticipate.

Photo Credit: James Jordan