The Florida Keys Mosquito Control Board has declined to give British firm Oxitec a contract to produce genetically modified mosquitoes for the Keys unless federal approval is given for their release.
That was a relief for opponents of the plan who worry about the potential dangers to public health, tourism and other unintended consequences.
"I don't feel there's a need for it," Mila De Mier said. The Key Haven resident's www.change.org petition to kill the plan had attracted 154,577 supporters as of Tuesday. "In most of these trials, you don't see the negative results until 10 to 15 years later."
The Mosquito Control Board has been considering using the modified Aedes aegypti mosquitoes to fight their potential to pass along dengue fever and chikungunya to humans. Both are painful and cause flu-like symptoms.
The Keys saw 27 cases of dengue in 2009 and 65 in 2010 but none since. There have been no reported cases of chikungunya in the Keys.
Oxitec has created a genetically modified male Aedes aegypti mosquito designed to control mosquito populations. The company says its male mosquitoes are reared in laboratories and released into the wild to mate with female mosquitoes. A gene is passed on to the offspring that kills it before it reaches adulthood.
The Keys project is being reviewed by the U.S. Food and Drug Administration, the Centers for Disease Control and Prevention, the Environmental Protection Agency and the U.S. Department of Agriculture.
Oxitec built a rearing facility at the Florida Keys Mosquito Control District building in Marathon in November. The CDC and FDA inspected the facility and process of rearing the mosquitoes in December. Mosquitoes born in the inspection were destroyed shortly afterward.
Test releases on Key Haven, just outside of Key West, is dependent upon FDA approval. FDA spokeswoman Juli Putnam said the agency will not support a field release until it has thoroughly assessed potential environmental impacts. A timeline for approval or denial is not set.
Supporters of Oxitec's plan say Aedes aegypti mosquitoes are becoming immune to Mosquito Control's chemicals and that genetically altered mosquitoes could significantly reduce the population of dengue- and chikungunya-carrying mosquitoes.
"There's a lot of misinformation out there," Commissioner Phil Goodman said. "People think this gene modification is creating some kind of toxic material in mosquito larva, which is not the case. Infectious diseases of mosquitoes are on the rise worldwide. We can't control the viruses so we have to control the population."
"The company is working with regulators to sell a product," De Mier said. "There's no peer review of Oxitec. This could negatively impact tourism."
Monroe County Tourism Development Director Harold Wheeler said the TDC does not have a stance on the issue.
Monday, Oxitec spokeswoman Chris Creese e-mailed links to 11 articles reviewing the company's modified mosquito. Nature Biotechnology, the Journal of Applied Ecology and Proceedings of the National Academy of Sciences are some of the periodicals to which Oxitec has submitted articles for peer review.
In 2012, the Key West City Commission passed a resolution preventing the release of genetically modified mosquitoes in city limits. City Commissioner Billy Wardlow echoed De Mier's concerns of unintended consequences.
"We're not sure what we're getting into and I don't really see the proof of it yet," he said. "I would rather see them released in another country until we know what exactly is going on with them."
Last year, Oxitec reported a 96 percent suppression of dengue-carrying Aedes aegypti mosquitoes in the village of Mandacaru in Brazil. Oxitec reported achieving similar results in Grand Cayman, an island comparable in climate to Key West.
"I believe this is good science and it's definitely a tool," said Mosquito Control Commissioner Steve Smith. "It'll be beneficial for mosquito control and not just here but throughout the world."
Oxitec will pay for the test runs at Key Haven should the FDA give approval. If approved for a Keyswide release, Mosquito Control will have to pay Oxitec. Smith said district Director Michael Doyle estimates the mosquitoes could cost $250,000 to $300,000 annually, similar to what the district pays annually for aerial larviciding via helicopter.