The study was conducted in a screen-enclosed, simulated village in Burkina Faso. They used a transgenic fungus developed by UMD team led by entomology Professor Raymond St. Leger and report that mosquito populations were safely reduced in the trial by more than 99 percent.
The team used Metarhizium pingshaense, a naturally occurring fungus that infects insects in the wild and kills them slowly. They engineered a strain of the fungus to produce a toxin that kills mosquitoes faster than they can breed. This transgenic fungus caused mosquito populations in their test site to collapse to unsustainable levels within two generations.
The toxin is an insecticide called Hybrid, derived from the venom of the Australian Blue Mountains funnel-web spider, approved by the U.S. Environmental Protection Agency (EPA) for application directly on crops to control agricultural insect pests. The scientists modified M. pingshaense so that it would produce and deliver Hybrid. To ensure this, they used a bacterium to transfer DNA into fungi. The DNA the scientists designed and introduced into the fungi provided the blueprints for making Hybrid along with a control switch that tells the fungus when to make the toxin. The modified fungus only produces the toxin inside the body of a mosquito. They tested the modified fungus on other insects in Maryland and Burkina Faso, and found that the fungus was not harmful to beneficial insects such as honeybees.
For more details, read the news release in UMD Right Now.