Mosquitoes are humanity’s worst enemy in the animal kingdom. Through the spread of diseases like malaria, encephalitis, and dengue fever, mosquitoes kill an estimated 725,000 people every year. And they’re incredibly annoying on top of it. That combination of super deadly and super annoying has led to science coming up with some pretty extreme proposals to deal with mosquitoes—usually involving playing god. One such proposal involves using CRISPR to genetically engineer mosquito populations to be infertile, eradicating the population within a couple generations of the tiny buzzing terrors. Now scientists have taken the genetic arms race against mosquitoes a bit further. In a paper published in the journal Science, researchers at the University of Maryland announced a new genetically engineered anti-mosquito weapon: a fungus with spliced in spider genes that produces spider venom. Mosquitoes can indeed drive people crazy.
Metarhizium pingshaense is a fungus that infects mosquitoes, and will eventually kill them but not fast enough. To quicken the process, the team inserted a gene from the Blue Mountains funnel-web spider, which makes the fungus produce spider venom once it enters the bloodstream of the mosquitoes. According to etymologist Raymond St. Ledger, a professor at the University of Maryland who led the research:
“We put into the fungus this specific gene from a spider which produces a toxin. But it only makes it when the fungus is swimming in insect blood.”
And it apparently works pretty well. The researchers tested their spider-fungus in a “MosquitoSphere” built in Burkina Faso, which was comprised of different compartments designed to act as stand-ins for the huts in which many in Burkina Faso live. Researchers released 1,500 of the mosquito species responsible for spreading malaria into each hut, some of which contained the unmodified fungus, and some that contained the modified venom producing fungus. It turns out that a venom producing fungus is pretty good at killing things. Within 45 days the mosquitoes were essentially erased. According to St. Ledger:
“Within two generations, the mosquitoes were basically gone. They’re finished.”
Predictably, not everyone is on board with with using this type of technology to combat mosquitoes. Nnimmo Bassey of the Health of Mother Earth Foundation, a Nigerian advocacy group, worries about the unintended consequences that could further hurt an already struggling part of the world. Bassey says:
“Fighting malaria is something that everybody should do. But fighting malaria through genetic engineering is dangerous.
“I’m heavily worried that Africans are the preferred guinea pigs for experimentation, and Africa is going to become a large laboratory for risky experimentation. We don’t want this to happen.”
According to Raymond St. Ledger, there’s a lot of testing and research that still needs to be done before even considering releasing the fungus into the wild, and he assures skeptics that it wouldn’t be released without the consent of the people it would impact. He says:
“Nothing is going to happen without the acceptance of the local people who would be exposed to the fungus, its benefits and any potential risks,”
So far, he says, the fungus doesn’t appear to pose a threat to any other species besides the malaria-spreading mosquito. And while there are serious concerns about free-for-all genetic engineering, malaria is a serious concern for much of the world. St Ledger says:
“If it just reduced the transmission of malaria by 5% that would still be hundreds of thousands of lives that benefited. And we think it could do quite a bit better than that.”
No one can say for sure what the long term consequences of this technology will be, but it’s certainly not going away and these conundrums are only going to increase in intensity. So what are we to do? The only answer is probably “hope we don’t screw it up,” but that’s the tightrope walk we’ve been walking since humanity first walked upright. Although that tightrope seems to be swaying in the breeze a little more these days.