With the aim of reducing rates of the mosquito-borne illnesses yellow fever and dengue, a pilot program will release 750 million genetically modified mosquitoes into the Florida Keys in 2021, thanks to approval by the barrier islands’ Mosquito Control District Board of Commissioners at a meeting on Tuesday (August 18).
The strain of GM mosquitoes, known as OX513A, is an altered form of Aedes aegypti created by UK-based biotech firm Oxitec. Released mosquitoes will be all male, as male mosquitoes do not bite and generally only feed on nectar. Thanks to a conditionally lethal genetic variant, when OX513A mosquitoes mate with wild females, their offspring should die before they are old enough for females to begin biting.
Over the last 10 years, Oxitec deployed these GM mosquitoes in the Cayman Islands and Brazil. This will be the first release of any GM mosquitoes in the US. The Centers for Disease Control and Prevention (CDC) and scientists at the University of Florida will oversee program.
“It’s gone extremely well,” Oxitec scientist Kevin Gorman tells the AP. “We have released over a billion of our mosquitoes over the years. There is no potential for risk to the environment or humans.”
A September 2019 study published in Scientific Reports concluded that female progeny of Oxitec’s GM mosquitoes were not dying off as intended in Brazil. Less than a week after it was published, an editor’s note about criticisms was appended. In May 2020, the paper received a formal Editorial Expression of Concern about the study design and erroneous or misleading claims.
Oxitec’s journey to releasing the mosquitoes in the Florida Keys has been several years in the making. The company commissioned 25 studies to obtain approval from the CDC, the US Environmental Protection Agency (EPA), and seven state and local agencies in Florida, Oxitec reports. The pilot program will target the Florida Keys because A. aegypti mosquitoes are invasive there and are increasingly resistant to insecticides meant to control their numbers, according to reports.
“The science is there. This is something Monroe County needs,” Jill Cranny-Gage, a supporter of the program, said at the Mosquito Control District’s meeting, according to the AP. “We’re trying everything in our power, and we’re running out of options.”
Oxitec has also received federal approval to release the mosquitoes in Texas, BBC News reports, but will face a similar battle to get the go-ahead from state and local agencies.