Buzz at designer mozzies

AUSTRALIAN researchers have embarked on a revolutionary project to create genetically-modified mosquitoes to help eradicate deadly diseases such as the zika virus and dengue fever.

A team at Macquarie University in Sydney hopes to release the designer mozzies into problem colonies to breed with females, which would then produce dead or sterile offspring. While mosquitoes might appear to do little aside from leaving humans with itchy bites, they play an important role in the ecosystem as a food source and even as pollinators.

But a number of species spread horrible diseases. The focus of the university’s project is the species Aedes aegypti, which can transmit viruses such as zika, dengue, yellow fever and chikungunya.

Symptoms range from joint pain to fever and, in extreme cases, death.

The problem mosquito lives in warmer regions, including South-East Asian countries such as Thailand and Indonesia which are popular with Australian tourists.

They also inhabit Latin America, subSaharan Africa and northern Queensland.

Dengue is an ongoing problem in Australia, with outbreaks occurring each year in northern Queensland.

In Australia last year, there were 59 confirmed cases of zika virus — which can cause birth defects — but all were contracted overseas.

CSIRO biologist Maciej Maselko, who is leading the project, said the number of dengue cases had grown exponentially.

“Over 100 million people are infected with dengue every year, and over 20,000 a year die from the disease,” he said.

Dr Maselko said as temperatures warmed due to climate change, the mosquito could find itself in new regions, such as Australia’s eastern states.

He said the project would create eggs in the laboratory that only carried males — which don’t bite humans.

In the event of a virus outbreak, the eggs could be sent to problem areas to hatch.

The resulting mosquitoes would then mate with females, passing on their altered genes with the outcome being dead or sterile offspring.

Dr Maselko said he hoped to begin field trials within three years and, if successful, deploy the designer mozzies in about five years.

Yellow fever and dengue vaccines existed, but in the case of dengue, doctors only recommended it upon a second infection, he said. It was often then that dengue was the most deadly. No vaccine existed for chikungunya or zika.