Biosecurity

The 5 most troubling questions scientists still have about Zika

Before last year, scientists knew very little about the Zika virus. As late as 2007, there had only been 14 documented Zika cases in the world. Research on the virus was so limited, in fact, that printouts of all the world's published literature could basically fit into a shoebox.

Suffice to say, researchers now have a lot of questions about Zika. After the mosquito-borne virus exploded around Brazil last year, moving on to most of Latin America and the Caribbean, an effort to better understand Zika was on. Here are the most pressing questions scientists are currently trying to tease out...