Public healthAnti-dengue mosquitoes to be released in Australia and Vietnam

Published 11 October 2010

Some 100 million people in the tropics get dengue fever each year, and 40,000 are killed by it; the virus’s range is expanding, and last week France reported its first locally acquired cases; Australian scientists will release mosquitoes called Wolbachia that infect the disease-carrying Aedes mosquitoes, and makes them less able to carry the dengue virus; the release will take place in Australia and Vietnam

Dengue fever-carrying Aedes mosquito // Source: axisoflogic.com

Mosquitoes infected with bacteria that stop them transmitting the dengue virus will be released into the wild next year, New Scientist reports.

Some 100 million people in the tropics get dengue fever each year, and 40,000 are killed by it. The virus’s range is expanding, and last week France reported its first locally acquired cases.

Scott O’Neill of the University of Queensland in Brisbane, Australia, and colleagues have found a fruit-fly bacterium called Wolbachia that infects Aedes mosquitoes, and makes them less able to carry the dengue virus. It also halves their lifespan — which is crucial, as only elderly insects transmit disease.

Wolbachia is passed on through the eggs of infected females, so only descendants of the released mosquitoes will carry it, O’Neill says. But dengue-free descendants should rapidly dominate, as Wolbachia-infected females have a competitive advantage: they can reproduce with infected or wild males, and wild females cannot.

Infected mosquitoes will be released in Australia and Vietnam.