Clouds of mutant mosquitoes may be filling the skies across some states if some scientists have their way. In May, the EPA granted the company Oxitec an experimental use permit to release millions of genetically modified mosquitoes every week over the next two years in Florida and Texas. The hope is that by overwhelming the wild population with mutants, mosquitos responsible for carrying dengue, chikungunya, yellow fever, and Zika viruses would collapse.
Females of the mosquito species “Aedes aegypti” are responsible for most of this viral transmission. Oxitec hopes to deploy genetically modified male insects in a lab; when they mate with wild females, their female offspring will die. Oxitec believes that continual, large-scale releases of these mutant mosquitoes would eventually cause the temporary collapse of a wild population, thereby ending the spread of disease.
Although the EPA approved the permit for Oxitec, state approval is still required. During the public comment period for the EPA approval, 31,174 people left comments opposing the project; 56 people wrote in favor of it. While the EPA approved it anyway, opposition from local residents could block state approvals. Oxitec attempted to release an earlier version of their geneticially modified mosquito, but significant opposition from residents led to that permit application being withdrawn in 2018.
However, an earlier attempt to control mosquito population this way backfired. Last year, an analysis showed an attempt to release modified mosquitoes produced mosquitoes that were even more resistant to mosquito control measures. In the experiment in Brazil, things started out well:the genetically-modified mosquitoes bred with their wild counterparts, causing a dip in the wild population. But over time, the wild female mosquitoes appear to be able to identify and avoid the unproductive males. Worse, hybrid varieties of mosquitoes were bred, creating combinations of Brazilian native mosquitoes and the Cuban and Mexican breeds that were genetically altered in the lab which created a new population more resistant to the original mosquito control measures.
Experts at Oxitec believe they worked out the “bugs” of their genetically modified mosquitoes. If permitting is granted, they could be releasing the mutant mosquitoes into the air in Texas and Florida in the coming weeks.