Genetically modified mosquitoes to be released in Florida Keys

In a controversial referendum on Election Day, residents of Monroe County, Florida, approved a trial release of genetically modified (GM) mosquitoes. This means that the United States could see genetically modified animals in the wild for the first time as early as spring 2017.

British biotechnology firm Oxitec developed the strain of GM male Aedes aegypti mosquitoes to be used in the trials. When these males mate with wild females, their offspring inherit a gene that kills them before they reaching maturity. Scientists hope that this will dramatically decrease the population of mosquitoes in the area, which can carry serious diseases such as Zika or dengue.

Successful trials have already been carried out in various locations. Oxitec has already lead trials in countries including Brazil and the Cayman Islands and shown that the release their GM mosquitoes lead to a reduction of the total population of Aedes Aegypti by over 90 percent. Additionally, in Piracicaba, Brazil, they demonstrated that the number of dengue cases decreased by 91% in areas where the GM mosquitoes had been released.

Despite the potential of controlling the spread of diseases with these modified mosquitoes, many residents in Monroe County have raised concerns about the long-term impact of this trial. Some residents fear that not enough is currently known about the risks involved in releasing genetically modified animals to guarantee that the trial will not incur damage to either the residents of the county or its environment in the long term.

For several years now Florida Keys Mosquito Control District’s Board of Commissioners has been trying to get federal approval for the release of GM mosquitoes. In August, the US Food and Drug Administration (FDA) finally greenlit the plan, stating that it should have no significant adverse impact on the environment. However, due to strong opposition, the Board decided to carry out two non-binding referendums to gauge public opinion. One was specifically for voters residing in Key Haven, where the mosquitoes were initially proposed to be released. The second referendum was for voters in the rest of the county.

A majority of people (58%) in the county approved the plan. However, in Key Haven, 65% were opposed to it. Therefore the Board has said that the mosquitoes will not be released in Key Haven as originally planned. An alternative location is still being decided but Oxitec says the trial is likely to be completed by the end of 2017.

(featured image courtesy of James Gathany, CDC)