Biotech company Oxitec have harnessed the mosquito’s reproductive instincts as a way to reduce their numbers. They have created genetically engineered male mosquitoes – which don’t bite – to be released to mate with females. Their offspring die before they can reproduce and before they can become transmitters of disease.

More than 90 million Oxitec mosquitoes have been released in approved trials worldwide, with an unprecedented level of success in controlling the dengue mosquito: in every trial the target mosquito population has been reduced by more than 90%.

 

Mosquitoes – the deadliest creatures on earth

Each year hundreds of millions of people are stricken by malaria and dengue, and now chikungunya virus is spreading like wildfire in the Americas. Without an available vaccine, public health groups around the world depend entirely on effective control of the mosquitoes spreading these terrible diseases. There’s one invasive species in particular that is to blame for epidemics of dengue, yellow fever and chikungunya – that’s the Aedes aegypti mosquito. This disease vector is in more than 100 countries and is still spreading.

 

Safe, effective and environmentally friendly mosquito control

Current control methods aren’t working well enough to reduce mosquito numbers below disease transmission thresholds. The mosquitoes are also becoming resistant to the pesticides we use, and these chemicals can affect helpful insects like bees and butterflies. This is why scientists at Oxitec developed a better way to control the mosquito – a method that is safe, effective, and environmentally friendly. The mosquitoes are given a self-limiting gene that prevents their offspring from surviving, and a colour marker to identify them. The males are released to mate with the females, reducing the population. The result is a non-toxic form of mosquito control that suppresses only the species making people sick. The genes do not spread, and once releases are stopped, the insects and their genes disappear from the environment. The Oxitec mosquito has suppressed the target Aedes aegypti population by up to 99% in field trials in countries such as Brazil, Cayman and Panama. These results combined with its light ecological footprint have captured the attention of mosquito control groups around the world.

Biotechnology breakthrough in Brazil

In Brazil the dengue burden is so great they’ve called in the army to help educate people on how to fight the dengue mosquito. Brazil has a lot of experience and expertise in tackling dengue and recognises the need for new approaches to complement and improve on current methods. Following successful trials, the national biosafety group (CTNBio) approved Oxitec’s engineered mosquitoes for use throughout Brazil. Piracicaba, a city in Sao Paulo state, will start releases of Oxitec mosquitoes at the end of this month.

 

Oxitec mosquito control nominated as top invention

The lead inventor of the Oxitec mosquito, Dr Luke Alphey, has been honoured as the UK’s sole nominee for a prestigious international award recognising this breakthrough in battling vector-borne diseases.

The dengue mosquito is the first target Oxitec put in its cross-hairs, and the species spreading malaria are next.