US researchers hacked a fungus to make it produce a toxin from an Australian spider that quickly kills mosquitoes.  While there's hope to use the technique for disease control, there are legitimate fears about unforeseen consequences.

According to a paper published in the journal Science, the University of Maryland researchers used transgenic engineering to make a fungus produce a toxin derived from the venom of the Australian Blue Mountains funnel-web spider.  

"Simply applying the transgenic fungus to a sheet that we hung on a wall in our study area caused the mosquito populations to crash within 45 days," researcher Brian Lovett said in a news release.  "And it is as effective at killing insecticide-resistant mosquitoes as non-resistant ones."

Malaria kills 400,000 people every year, and it's only one of a myriad of mosquito-borne diseases that vex tropical areas, often in poor countries without the resources to fight them.  But the researchers tested it outside the lab in a screen-enclosed setting in West Africa designed to mimic a village.  The idea of transgenic fungus getting out into the wild without comprehensive testing of its impact frightens many.

"This study raises several urgent concerns," said Dana Perls of the environmental group Friends of the Earth.  "Genetic engineering of fungus could have problematic negative public health impacts and unpredictable ripple effects on ecosystems, affecting pollinators, bats, and bees.  Like with all genetic engineering, this needs to be addressed with great caution."