Tuesday, March 8, 2011
Flightless mosquitoes may curb dengue
Genetically altered mosquitoes that cannot fly may help slow the spread of dengue fever and could be a harmless alternative to chemical insecticides, U.S. and British scientists said on Monday. [Feb 22, 2010]
They genetically altered mosquitoes to produce flightless females, and said spreading these defective mosquitoes could suppress native, disease-spreading mosquitoes within six to nine months.
There is no vaccine or treatment for dengue fever, which is endemic in the tropics and is particularly prevalent in Asia and the western Pacific. The disease, which causes severe flu-like symptoms and can kill, is spread through the bite of infected female Aedes aegypti mosquitoes.
"This could be the first in a new wave of products that might supplant insecticides," researcher Anthony James of the University of California, Irvine, said in a telephone interview.
James's team, including a group from the British biotechnology firm Oxitec Ltd., altered mosquito genes to disrupt development of the insects' wing muscle.
The genetic modification grounded only the virus-carrying females and did not affect the males' ability to fly, they wrote in the Proceedings of the National Academy of Sciences here
The idea would be to distribute tens of thousands of eggs that would hatch out these genetically modified males, that would proceed to create a new generation of flightless, and thus doomed, daughters.
Because eggs are so small and easy to distribute, there would be far more genetically modified mosquitoes than natives, so they could in effect blot out the dengue-carrying population.