Aedes aegypti: the invasive mosquito in Florida that carries deadly diseases. Photo by James Gathany, c/o the CDC
In the past few days, a new GMO scandal has hit the headlines. The UK biotech firmOxitec has proposed the release of special genetically modified mosquitoes in the Florida Keys to help with current mosquito control efforts. Or, according to the media:
Millions of GMO mosquitoes to be released in Florida Keys if Oxitec gets its way
Florida, Meet Genetically Modified Mosquitoes, Which Are Coming Your Way By The Millions
The Washington Post actually called them genetically modified killer mosquitoesin their headline, warningthat they may attack Florida Keys. George Dvorsky for io9cautionsthat Millions Of Mutated Mosquitoes Could Be Unleashed In FloridaOn Purpose. Its safe to say news of the FDAs deliberations on whether to allow these Frankenstein mosquitoes are causing quite the stir. Theres even a Change.org petition to fight the release,with nearly 140,000 signatures.
While these mosquitoes are genetically modified,they arent cross-bred with the herpes simplex virus and E. coli bacteria (that would be aninterkingdom mnage trois!)and no, they cannot be used to bite people and essentially make them immune to dengue fever and chikungunya (they arent carrying a vaccine!). The mosquitoes that Oxitec have designed are what scientists call autocidal or possess a dominant lethal genetic system, which is mostly fancy wording for they die all by themselves. The males carry inserted DNA which causes the mosquitoes to depend upon a dietary supplement thatis easy to provide in the lab, but not available in nature. When theso-called mutantsbreed with normal females, all of the offspring require the missing dietary supplement because the suicide genes passed on from the males are geneticallydominant. Thus, the offspringdie before they can become adults. The idea is, ifyou release enough such males in an area, then the females wont have a choice but to mate with them. That will mean there will be few to no successful offspring in the next generation,and the population is effectively controlled. Oxitec hopes to release millions of autocidalAedes aegypti mosquitoes in the Keys because that species is a vector for deadly diseases, and Oxitec is hopingthat reducing mosquito populations will protect residents. You would think that would be a good thingbut the headlines and rhetoric of the media suggest otherwise.
The first concern seems to be that theres no need for a new method of mosquito control. If I knew that this was a real risk and lives could be saved, that would make sense, the quote from the Associated Press article reads,But there are no problems. Why are we trying to fix it? Why are we being used as the experiment, the guinea pigs, just to see what happens?. Actually, contrary to the esteemed opinion of Key Haven resident Marilyn Smith that is being includedin every article verbatim, Floridiansshould be at least a little concerned about the two virusesthat the Oxitec mosquitoes are largely aimingto fight:dengue andchikungunya. Both are nasty emerging diseases that, thanks to a ever-more-connected globe and climate change, are becoming more of an issue in the United States every year.
What worries public health scientists, entomologists, etc. is that our environment and ecology, particularly in the tropical Keys, make us very vulnerable to the threat of disease, explains vector ecologist Tanjim Hossainfromthe University of Miami.Dengue, for example, was well established in the U.S. for centuries.
Chikungunya is a relative newcomer in the infectious disease world. The first known outbreak occurred in Africa in 1952it wasnt until 2013 that it first appeared in the Americas. But while it lacks the long history and high death toll of dengue, its quickly becoming a major concern.Infections are accompanied by high fevers and debilitating joint pain that can last weeks. And guess what?According to the CDC, Florida is the only state in the US which has had locally-acquired cases. The CDC would rather stop chikungunya in its tracks before it settles in the US permanently, and thus, theres a major focus in Florida right now to knock out the mosquitoes that transmit it. Conveniently enough, itsthe same species that transmits dengue:Aedes aegypti, which means control efforts can get twice the bang for the buck. And even better, this is a species that isnt native to Florida; it doesnt belong there, and there are no native species that rely on these invaders to survive. So there wont be negative environmental impacts in Florida if Oxitec (or the government in general) is successful inremoving all of theA. aegyptithere. There simply wont.
Dengue, on the other hand, is much more of an immediate concern. Thevirus is responsible for one hundredmillion infections and tens of thousands of deathseach year. While its true that only a few of these are from the US, in recent years, the number of local cases hasbeen increasing, and the Florida Keys is one of the areas most at risk of an outbreak. In 2009, the CDC found that more than 5% of the people testedin the Keys had recently been infected with dengue. Finally, after a dengue outbreak in 2009-2010, theFlorida Keys Mosquito Control District(FKMCD) stepped up their anti-mosquito game, and began implementing more rigorous control methods, including house inspections and increased truck and aerial pesticide sprays. Thats why there hasnt been a dengue outbreak sincenot because theres nothing to fear. After all, Marin County residents know the danger all too well, as they justhad an outbreak in 2013. And while everyone seems to be worried about what kinds of terrible things the mutant DNA from these autocidal mosquitoes will do, few seem concerned with the fact that theyre constantly being coated in pesticides instead. The pesticides being used are the safest available, but even still,ecologists have raised concerns about effects on non-target wildlife, including potential negative impacts on the beautiful aquatic habitats that draw tourists. If the Oxitec mosquitoes were used, they would reduce the mosquito populations without any dangerous chemicals: theyve already shown that, unlike pesticides, the proteins produced to kill the larvae dont have off-target effects, and dont harm potentialpredators if they eat thelarvaebefore they die.
More here:
Journalists vector GM fears as FDA considers Oxitec's Keys mosquito plan