Average Annual Death Toll: 725,000
We usually think of mosquitos as annoying, buzzing, blood-eaters. They also happen to be the deadliest animals on the planet. These guys carry malaria, which alone caused an estimated 584,000 deaths and afflicted nearly 200 million people in 2013. The mosquito-borne disease reportedly threatens half of the world's population. That's not to mention other nasty things mosquitos carry, like dengue fever, yellow fever, and encephalitis.
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