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Today, scientists don’t need mongoose or toads for pest control. In some cases, they can just tweak the genes of the animal or insect they’re trying to vanquish. There’s good evidence to support the idea that genetic modification of the Aedes aegypti mosquito, for example, could help dramatically reduce its population.

Aedes aegypti is the main vector of the Zika virus, a mosquito-borne illness that has public-health officials around the world on edge. In Brazil, hundreds of babies born to Zika-infected mothers have suffered severe birth defects since last year. Public-health officials, who are calling Zika a global emergency, estimate that number will climb well into the thousands in Brazil alone. In the United States and elsewhere, as mosquito season ramps up, people are bracing for additional outbreaks.

At the same time, in a small Florida community near Key West, the Food and Drug Administration is accepting public comments on a proposal from the biotechnology firm Oxitec to introduce genetically modified Aedes aegypti males into the local mosquito population. If Oxitec is successful, its technology could help wipe out Aedes aegypti in the region—and protect people from Zika transmission there.

Oxitec’s plan is to inject mosquito eggs with DNA that contains lethal genes, then release the genetically modified males from that batch of eggs so they can mate with wild females. (Males don’t bite; so releasing only males is a way to make sure the release of these insects doesn’t contribute to the spread of disease.) The offspring of these lab-tweaked males and wild females, having inherited the altered DNA, cannot survive to adulthood. If all goes as planned, the mosquito population should shrink as a result. There’s already good evidence that shows Oxitec’s approach can work. Field tests in Piracicaba, Brazil, resulted in an 82 percent decline to the mosquito population over an eight-month period, Oxitec says.

And there’s a compelling need for trying to control the mosquito population this way. Aedes aegypti don’t just spread Zika, but also dengue fever, yellow fever, and chikungunya virus. “About 40 percent of the global population is at risk [from] this species,” said Andrew McKemey, an entomologist and the head of field operations for Oxitec. “It’s kind of the rat of the mosquito world.”

Besides all that, existing mosquito controls clearly aren’t enough—especially in the United States, where the fight over state and federal Zika funding has devolved into petty politicking, with Republicans blocking emergency funding to fight the disease. “My opinion on how we should proceed is we should aggressively pursue Aedes aegypti control—but we haven’t started that yet, and I’m not sure there’s been the political will to do it,” said Peter Hotez, the dean of the National School of Tropical Medicine at Baylor College of Medicine. “It’s very labor intensive. It requires getting rid of standing bodies of water, putting up window screens, and doing house-to-house insecticidal spray.” The coordinated effort that’s necessary, Hotez says, goes beyond anything the U.S. has ever done to control mosquitoes in the past. As temperatures warm and mosquitoes emerge, it may already be too late for at-risk cities in the states to take the precautions Hotez describes. Which is part of why the promise of genetically modified mosquitoes is so appealing to those who support the idea.