Stopping the spread of Asian tiger mosquitoes to Australia
Mosquitoes in the Indo-Pacific spread diseases like malaria, dengue, and Japanese encephalitis and cause over 23,000 deaths each year. Globally, dengue alone infects more than 390 million people every year and threatens billions more across the tropics. Climate change, rapid urbanisation, trade and human movement are exacerbating the problem, particularly in developing countries across the Indo-Pacific.
The Asian tiger mosquito (Aedes albopictus) is the most invasive mosquito species in the world, a major spreader of human viral diseases such as dengue, Zika and chikungunya, and represents a significant daytime nuisance biter, hence its nickname 'the BBQ stopper'. It is wide-spread across the Indo-Pacific region but is yet to establish on the Australian mainland. If it were to do so, the Australian population and sections of the economy would be at risk from these deadly mosquito-borne diseases.
A safe, effective and self-limiting strain
CSIRO has entered into a collaboration agreement with Oxitec Ltd (UK) to develop an Asian tiger mosquito solution to protect Australian communities from this deadly threat.
This project will see CSIRO and Oxitec develop a highly targeted, non-toxic, insecticide-free, and environmentally sustainable method for controlling invasive Asian tiger mosquito populations.
Only female mosquitoes bite and are capable of transmitting disease. So, reducing the female's ability to successfully reproduce is the key to controlling Asian tiger mosquito populations. We aim to do that by creating a safe, effective and self-limiting strain of male Asian tiger mosquito that – when it mates with wild Asian tiger mosquito females – produces non-biting, non-disease transmitting males. A self-liming gene prevents female offspring from surviving long enough to reproduce.
Regular releases of these males into a wild population would prevent the production of wild female mosquitoes, resulting in suppression of the target population by greater than 90 per cent.
The self-limiting mosquitoes are safe for humans, animals, crops, and the environment. They leave no long-term trace as their genes are only passed on for a few generations. Halting releases of self-limiting males will result in the wild mosquito population returning to normal after around 10 weeks.
The insects will also carry a fluorescent marker gene which, when viewed under special light filters, will allow us to distinguish the self-limiting insects from local invasive counterparts. This improves efficiency and simplifies monitoring.
Through this work CSIRO aims to improve the health of communities in Australia and the Pacific region, reduce public health impacts, develop more sustainable pest control, empower local communities, and limit the spread of invasive mosquitoes and the diseases they transmit, within the region.
CSIRO operates within strict guidelines and government regulations around gene technology research. This ensures the safety of the community and the environment, and that rigorous scientific practices are followed.