How the Zika virus causes birth defects

New research provides the first direct evidence that Zika virus causes severe birth defects, and explains exactly how it does so

"I lifted up my T-shirt to check on what I thought had just been a small heat rash," writes BuzzFeed correspondent Ali Watkins. "It had shown up along the right of my back, extending out from a handful of mosquito bites I had picked up" it had seemed relatively tame [but] now, it was inching across the front of my stomach and down my legs... Meanwhile, my right eye was inflamed and bright red, almost akin to a busted blood vessel."

Watkins is describing the symptoms of a Zika virus infection that she contracted on a recent trip to Mexico. For many people, infection with this mosquito-borne virus causes an illness with symptoms just like those experienced by Watkins: fever, skin rash, joint pain and conjunctivitis. For others, these symptoms are so mild that they go completely unnoticed.