The death toll from diseases carried by mosquitoes is so huge that scientists are working on a radical idea. Why not eradicate them?

Mosquitoes kill more humans than any other animal and were linked to roughly 500,000 deaths in 2015, mostly from malaria. For more than a century, humans have used bed nets, screens and insecticides as weapons, but mosquitoes keep coming back. They are now carrying viruses like Zika and dengue to new parts of the world.

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