Mosquitoes: the most hated, seemingly useless insects on the planet. Their itchy, irritating bites and annoying hum of buzzing wings is enough to drive a person crazy. The hundreds of diseases they carry are very harmful to humans. But what if we could fight fire with fire? Scientists at Oxitec have been working to genetically modify mosquitoes to fight the Zika virus and the citizens of Florida voted to release millions of these tiny, genetically modified mosquitoes into their state as a trial to eradicate virus-carrying insects.

Florida health authorities have diagnosed sixteen cases of the Zika virus spread by local mosquitoes, and have resorted to ramping up an aerial pesticide spraying of the Miami area. The problem with pesticides is that they are not always effective and can damage the environment. Oxitec’s mosquitoes are said to have little to no impact on the environment and are very effective in eradicating the virus. To start, the mosquitoes will be released in the Florida Keys, where scientists predict that these genetically modified insects will kill off nearly ninety percent of Zika-carrying mosquitoes. In order to do this, scientists at Oxitec have taken millions of male mosquitoes and placed an engineered gene inside them that will cause their offspring to die before adulthood and end their ability to spread the virus through biting humans.

Like all trials, there are some uncertainties. Many officials question how effective the study will be in both the long and the short run. They claim that if they get rid of an entire species of a mosquito that quickly, another species, the Asian Tiger Mosquito, will move in and still carry the virus. “We’ve seen elsewhere where there is distribution of these two species that when there’s a vacant niche Asian Tiger Mosquitoes will move in, and it’s a competent vector of the same viruses,” says Phil Lounibos, an entomologist who studies mosquito-human disease transmission at the University of Florida. Also, in order to completely contain the virus, the male mosquitoes must mate several times to deaden the gene pool, and studies have shown that even then some larvae will still make it to adulthood.

Nonetheless, the Florida Keys is the perfect place to conduct the experiment. For one, it keeps the insects isolated on the island and residents of the Florida Keys are allowed to end the trial whenever they feel necessary. “As soon as the experiment is over, it’s up to the Florida Keys and their commissioners whether they want to implement this on a larger scale,” says Lounibos. If they do, they shouldn’t wait too long; any waiting period after the end of the experiment opens the area to remigration of Aedes aegypti from the Caribbean or mainland Florida.

A male Aedes Aegypti Mosquito, photo via Wikimedia Commons.

The Zika virus has no known cure and poses the biggest threat to pregnant women. The virus puts pregnant women in danger because it has been known to cause multiple birth defects in the child’s brain. The World Health Organization has declared a global health emergency over Zika’s link to microcephaly, a condition marked by abnormally small head size that can lead to severe developmental problems. The agency has suggested that alternative approaches to fighting mosquitoes that carry the virus might be an important way to suppress mosquito populations. Symptoms of the Zika virus include fever, rash, joint pain, and red eyes, but many people with the Zika virus won’t even have symptoms. Over the past year, Zika has spread through most of South America and is slowly making its way to the United States. If scientists can stop the spread of this disease in the Florida Keys, it will prevent a contamination in America.