750 million GM mosquitoes set for release in Florida Keys

The project will involve the release of a GM mosquito (Aedes aegypti) called OX5034, which has been adapted to pass on a protein which kills female offspring before they can hatch and grow large enough to bite while male mosquitos mature to adulthood and continue to pass along the modified genes. Only female mosquitos bite for blood (in order to mature eggs); males are not a carrier for disease.

It is hoped that this will suppress spread of mosquito-borne diseases such as dengue and Zika.

The project is being organised by Oxford-based Oxitec, which carried an OX5034 trial in Brazil in 2018. Oxitec reported that this achieved up to 96 per cent suppression of the disease-transmitting mosquito populations while no harm was caused to other insects.

After many years of deliberation – during which Oxitec put forward an alternative “friendly mosquito” – the project won approval from state and federal authorities and has now received approval from local authorities. The mosquitoes will be released across Florida Keys in 2021 and 2022, and also in Harris County, Texas. This will mark the first population suppression effort using GM mosquitoes in the US.

“We’re looking forward to working hand-in-hand with the Keys community to demonstrate the effectiveness of our safe, sustainable technology in light of the growing challenges controlling this disease-spreading mosquito,” said Oxitec CEO Mark Carnegie-Brown.

Population suppression using GM organisms (including gene drives) have been touted as an alternative to mass use of insecticides to control insect disease vectors; massive efforts to control Aedes aegypti populations in Florida Keys have reportedly been ineffective.

The proposals have been opposed by a coalition of advocacy groups, including Friends of the Earth and the International Center for Technology Assessment and Center for Food Safety.

In a statement, the latter’s policy director Jaydee Hanson commented: “With all the urgent crises facing our nation and the State of Florida – the Covid-19 pandemic, racial injustice, climate change – the administration has used tax dollars and government resources for a Jurassic Park experiment.”

“Now the Monroe County Mosquito Control District has given the final permission needed. What could possibly go wrong? We don’t know, because [the Environmental Protection Agency] unlawfully refused to seriously analyse environmental risks, now without further review of the risks, the experiment can proceed.”