Sterilized GM mosquitoes released in largest field test to combat dengue in Brazil


In Jacobina, a Brazilian farm town where legions of people have suffered from dengue fever, a campaign is fighting back, releasing swarms of mosquitoes engineered to wipe out their own species.

As workers open plastic containers allowing millions of newly hatched Aedes aegypti mosquitoes to spread their wings and flutter into the sky in the largest ever field test, it seems counterintuitive. After all, this is the same pesky bug that transmits the dengue virus through a human-to-mosquito-to-human cycle that’s surprisingly difficult to break.

Conventional public health campaigns to fight dengue by fumigating and adding larvicide to water tanks have had little impact because Aedes aegypti often live and breed inside homes and develop resistance to insecticides. Bed nets used while sleeping are useless because the mosquitoes that carry dengue bite during the day, not at night. Education campaigns urging people to wear repellent and long sleeves have fallen on deaf ears.

The mosquitoes contain a lethal gene, but survive in the Moscamed lab with the help of the antibiotic tetracycline. Once they reach larval stage, the males are separated from the slightly larger females, which are destroyed. The males — which don’t bite — are released so they can mate with wild females. Their offspring inherit the lethal gene and die before they can reproduce because, in the wild, there is no tetracycline.

Read the full, original article: This is the biggest swarm of genetically modified mosquitoes ever set free

  • Paulo Andrade

    (National Technical Biosafety Commission) of Brazil has just authorized the
    marketing of transgenic mosquitoes (April 10, 2014). Strain OXC513a of Aeddes
    aegypti, developed by Oxitec, can now be employed to combat dengue across the
    Brazilian territory.

  • Dee Chips

    Sounds like a good idea…but has anything been done also to test the birds of other insects like dragonflies that might eat these genetically modified mosquitoes….do they either die or several generations later become sterile…longer term impact studies would seem to be called for…just wondering…trying to get more clear on the whole issue and keep an open mind regarding both pro’s and cons…any one know of such studies?

    • Dee, there is no biological or genetic reason that anything that ate a genetically modified mosquito would have any unusual reactions. Genetic modification is a process, not a ‘final product’. Mosquitoes are genetically modified all the time through conventional breeding. The biotech mosquitoes just have a gene tweaked would result in nothing potentially harmful happening. You cannot study ‘nothing.’

  • d marino

    This is insanity. The sinister buffoon scientist or researcher that came up with this idea is no better than a Dr. Frankenstein. Attempting to wipe out an entire insect could result in huge repercussions on the ecosystem. Trickle down effect on all animal and plant life can backfire. The bats and the birds die. Then more birds and monkeys die. Then the freaking humans. All because someone might get bitten. These mosquitoes have been on the planet for how long? Has the mosquito wiped out an entire population of humans yet? No. People get diseases and recover. Some people cannot recover due to a very weakened immune system or also having other serious illnesses. That is the way nature works. Find a treatment to ease the suffering of those that get bitten not eliminate a complete species.