Researchers partly funded by NHLBI revealed that the Zika virus showed up in the Americas several months, perhaps even years, before anyone realized it. In the study published in the journal Nature the researchers mapped 54 complete or partial genomes of DNA of the virus in order to track its spread through the continent.
Los Angeles Times: What the DNA of the Zika virus tells scientists about its rapid spread
Wired: Virus Hunters Draw a Map of Zika’s Spread With DNA
The San Diego Union-Tribune: Zika struck Florida up to 40 times before detection
TheScientist: Tracing Zika’s Spread Through Genetics
ScienceNews: The Zika epidemic began long before anyone noticed