By Lizette Alvarez

New York Times

KEY HAVEN, Fla. >> To live here, along this chain of tiny islands, a place vulnerable to hurricanes and steeped in the lore of piracy and smuggling, requires a blend of carefree eccentricity and go-it-alone grit.

So when, several years ago, the Florida Keys Mosquito Control District offered up the peninsula of Key Haven, a tiny suburb of Key West, for the first United States test of genetically modified mosquitoes built to blunt the spread of dengue and Zika, it was only a matter of time before opposition mounted.

Today, even as federal officials have told pregnant women to stay away from parts of Miami-Dade County because of the Zika virus, Key Haven’s hardened position against the trial — or the experiment, as they call it — is hard to miss amid the bougainvillea and hibiscus flowering on lawns here. “No Consent to Release of Genetically Modified Mosquitoes,” red-and-white placards declare.

“People here can survive what nature throws at them,” said Gilda Niles, 64, who arrived in Key West from Cuba in 1967 and moved to Key Haven in 1980, when it was just a plot of earth with cheaper land, water on three sides and more space. “Hurricanes, bring them on; long-timers here seldom evacuate. Mosquitoes, well, that’s the price of paradise. Zika, this too shall pass, like dengue. But science and government, I’m not so sure about.”

After lobbying the county commission and the mosquito control district for a say, Key Haven residents will get a chance to vote on whether they favor allowing Oxitec, a British company, to release its genetically modified mosquitoes in their community of 440 homes. Florida Keys residents will also vote on a referendum that asks whether they want the mosquitoes anywhere along the chain of islands in Monroe County. Both referendums will appear on the Nov. 8 general election ballot.

Because the referendums are nonbinding, a no vote by residents would not preclude the five-person mosquito control board from moving forward, but it would certainly make it politically difficult.

The debate has swirled and intensified over four years, prompting small rallies, a large online petition campaign, sharp exchanges and the opposition of the Key West City Commission. It has even added a shot of adrenaline to the typically staid race for seats on the mosquito control board. But the controversy over the trial has taken on new urgency this month with widespread attention to the spread of Zika.

Florida now has 37 cases of active Zika transmission, all of them in Miami-Dade County. Another 494 Floridians have been infected abroad. The virus, while largely harmless, is a serious threat to pregnant women because it can damage a fetus’ brain, causing a condition called microcephaly. Zika can also be sexually transmitted.

Oxitec scientists said they had reduced the population of Aedes aegypti mosquitoes, which carry the virus, by 90 percent or more in other areas where the company’s modified mosquitoes have been released, including Brazil. The male mosquitoes carry synthetic DNA as larvae. They are hatched and then released as adults to mate with females (who do all the biting) in the wild. The DNA infuses their offspring with too much protein, causing them to die.

Pesticides in the Keys, which have one of the best mosquito-control programs in the world, have about a 50 percent success rate with Aedes aegypti, which are rapidly becoming immune to some products, officials in the Keys said.

Still, even the genetically modified mosquitoes would not be a quick fix. The trial would most likely last four to six months, but could go as long as 22 months if big storms or hurricanes interfered, said Hadyn Parry, the chief executive of Oxitec.

But in the lower Florida Keys, as is true in large areas of the United States, skepticism of corporate interests and scientific findings abounds. Many residents are dubious about studies showing that genetically modified mosquitoes are not harmful.

“This is Jurassic science,” said David Berthier, a Key West resident and one of the critics of the experiment. “People distrust this because there is so much corporate spin.”

Phil Goodman, the chairman of the Florida Keys Mosquito Control District Board of Commissioners, said he opposed the referendum because the board was elected to make these kinds of hard choices “from a position of knowledge, and not emotion.”

“The opponents have very little information, and they are led by a few people who are non-science-based,” Goodman said. “We have tried to explain the real answers to them. They are not interested in the truth.”

Goodman said scientists and regulators — including the Food and Drug Administration, the Environmental Protection Agency and the Centers for Disease Control and Prevention — had concluded that there is no evidence that the mosquitoes are harmful to people, animals or the environment. For this reason, the FDA granted final approval to the trial this month.

It was the mosquito control district that recruited Oxitec as a result of Key West’s small dengue outbreak in 2010. The district chose Key Haven as the site because it had so many of the requirements needed to keep track of the mosquitoes, which normally fly a few blocks: It was small, it was a peninsula and it had plenty of other Aedes aegypti to serve as mates.

“People portray us as some corporate company that has chosen the Keys,” Parry said. “We chose the Keys because the Keys chose us.”

In Key Haven, where imposing houses mix with the original working-class variety and cars park next to boats in the driveways, most residents are not backing down. Jitka Olsak, who was at the small park in the neighborhood with her two children and her dog, said Zika did not scare her as much as scientists tinkering with animals. Like others, she fears that some of the genetically modified female mosquitoes — a small percentage are expected to slip through the cracks and be released, scientists said — will bite people and cause unexpected consequences.

Plus, Key Haven does not even have Zika.

“We are not going to be laboratory mice,” said Olsak, who moved to Key Haven 10 years ago from the Czech Republic. “Nature takes care of its own things.”

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