U. S. and British scientists said on Monday that genetically altered mosquitoes that would not be capable of flying would help curbing dengue that is widely prevalent in Asia and western Pacific.

These mosquitoes that cannot fly may slow down the spread of dengue fever and could also prove to be a harmless alternative to chemical insecticides.

This genetic modification produces only female mosquitoes, scientists said and these could be effective in repressing disease-spreading mosquitoes within six to nine months.

As of now, no vaccine exists for treating dengue, widely prevalent in tropics.

Researcher Anthony James of the University of California, Irvine, said, "This could be the first in a new wave of products that might supplant insecticides."

World Health Organization states that about 50 million cases of dengue fever happen every year, mostly in Africa and southeast Asia.

James's team, including a group from the British biotechnology firm Oxitec Ltd., altered mosquito genes in such a way that development of insect’s wings is hampered.

The genetic modification will effect only female mosquitoes as they carry the virus.

Scientists said, “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.”

Oxitec's Luke Alphey, who led the study, further added, "The technology is completely species-specific, as the released males will mate only with females of the same species."