State Approves Trial For New Mosquito Control Method

The first Florida trial of the Wolbachia bacteria to combat Aedes aegypti mosquitoes has been approved for the Florida Keys.

Aedes aegypti are the mosquitoes responsible for transmitting the Zika virus. They can also carry dengue fever and chikingunya.

The Florida Department of Agriculture and Consumer Services approved MosquitoMate's request for a trial of Wolbachia as a method of mosquito control in the Florida Keys.

A trial of genetically modified mosquitoes has received approval from the FDA, but has been delayed after significant public opposition. Monroe County voters will weigh in with a nonbinding referendum vote next month. The final decision is up to the Florida Keys Mosquito Control Board.

Leading opponents of the GMO mosquito trial said they were pleased that a Wolbachia test has been cleared to go ahead.

"It's a benign, effective process that has gone through significantly more scrutiny than genetically modified mosquitoes," said Ed Russo, chairman of the Florida Keys Environmental Coalition. "Wolbachia has the broad support of all the people in the Florida Keys."

The trials are expected to start next March and will take place in either Key Largo or Stock Island, depending on whether the GMO mosquito trial goes forward. Stock Island is close to Key Haven, site of the proposed GMO mosquito trial.

Stephen Dobson, president of MosquitoMate, said it makes sense to start the trial just before the rainy season, when mosquito populations grow.

"This time of year, everything's going down," he said. "It would just make it very complicated to try and interpret the results."

The Florida Keys Mosquito Control District has been working with MosquitoMate since 2012. That's one reason the trial is taking place in Monroe County — which has had five reported cases of Zika, all travel-related — and not in Miami-Dade, which has had ongoing local transmission of the disease.

The Keys have an independent, well-funded mosquito control program compared with most counties on the mainland.

"You have to have a strong collaborator, boots on the ground locally," Dobson said. "You have to have a well trusted abatement district who's there, who can work with the people and explain the technology, for this to succeed."

Dobson said the company has begun talks with Miami-Dade County now that the urgency of combating Aedes aegypti has dramatically increased.

Wolbachia is a naturally occurring bacteria that affects many insects — but doesn't normally occur in Aedes aegypti mosquitoes. When a male Aedes aegypti mosquito with Wolbachia mates with a female, the eggs don't hatch.

The new approaches are welcome because fewer insecticides and pesticides are available to combat mosquitoes, said Beth Ranson, spokeswoman for the Florida Keys Mosquito Control District. And the Aedes aegypti population in Key West is showing signs of resistance to some of the existing treatments, she said. 

"We're going to look at every available tool that's out there that's approved for us to try," she said.

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