. >> reporter: these mosquitoes are created by a british company called oxitec. karla tepedino runs the supply line. >> this is the biggest mosquito factory in the whole world we are producing two million of male mosquitoes per week. >> reporter: you could say it's "in-gene-ious." oxitec technicians insert a synthetic gene into mosquito eggs that causes them to create too many proteins. it's a fatal disease. while they are still in the lab, they're given an antidote that keeps the disease at bay. once they are released, they find a female and breed. but their offspring inherit the gene that causes the fatal disease. with no antidotes in the wild, they die not long after they are hatched before they can breed. >> the beauty this technique is that it can reach the mosquitoes where no other technique can find it. we are using mosquitoes to fight themselves. >> reporter: it appears to be working. and here's how they know: in addition to the killer gene, they add one that's a special marker. only the genetically modified mosquitoes will glow under a special light. thi

perception going to be to somebody like that who is giving it away for free versus a company like oxitecrying to make a living. >> yes, we're talking about eradicatingaterrible class of diseases, but there is a genie out of the bottle with this gene drive. as soon as you make the decision to release these mosquitos into the environment, what's going to happen is going to happen. there's no going back >>> the public seems to be afraid of g.m. organisms because they don't know much about them >>> they have fascinating mitigation strategies to keep on top of how they're doing. they're starting in a remote place and see what happens there. when we have a better understanding of how these animals impact the environment we can take it elsewhere >> we have all seen jurassic park, all right? >>> they will naefr leave the island >> this mosquito has spread all over the world. it is piggy backing on humans, but still an island is a relatively safe place. these issues raise a tonne of questions which we here at techknow, we're going to stay on top of. that's it for this episode. see you next time.

mosquitoes that biologist cecelia kosman releases are genetically modified by a british company, oxitec, to contawn a lethal gene. in order to survive, the engineered insects need an antibiotic, which they receive as they're raised in the lab. then they're released so they will mate in the wild. outside the lab, without the antibiotic, they die, as do their offspring who carry the same lethal gene. >> if fighting mosquito, we are fighting every disease that a mosquito can transmit. >> reporter: the aedes aegypti any standing water-- drainage ditches, the bottom of a trash bag, a simple puddle. breeding sites are constantly monitored. a secretary gene alteration makes the larvae fluorescent so they're easy to count. the company says the larvae population in the area dropped 82% in less that a year. >> we know we can eradicate the aedes aegypti mosquito. >> reporter: dr. peter hotez is one of the leading tropical disease experts in the world. he said an aggressive international campaign led to the near eradication of aedes aegypti back in the 1970s, but the species has rebounded. >> i thi