The virus showed up months—or even years—before anyone realized it was there. And Miami proved to be the perfect gateway into the U.S.
In April 1947, researchers in Uganda discovered a new virus in the blood of a feverish monkey. The following January, they found it again—this time in mosquitoes buzzing through the forest where the monkey lived. The virus eventually took the forest's name: Zika. In the following decades, Zika was largely forgotten, as other newly discovered viruses hogged the limelight, including those that cause measles, the common cold, hepatitis, AIDS, Ebola, SARS, and more. But Zika hadn't gone away. In fact, it was on the move.
In May 2015, a huge outbreak of Zika began in Brazil, infecting more than 200,000 people. From there, the virus spread explosively to dozens of other countries in the Americas, and all 50 U.S. states. And since Zika can cause microcephaly—a birth defect characterized by small head size—it caused fear wherever it landed. The outbreak has now abated, and just two weeks ago, Brazil finally ended its state of emergency. But as before, Zika hasn't gone away. With summer approaching and mosquito populations rising, the key to predicting and controlling Zika's future lies in understanding its past.
