Brian Resnick – Vox, 02/01/2016
Up until recently, Zika was a little-known virus mostly confined to small islands in the Pacific Ocean and a few African nations. So how did it come to spark an “explosive”world health emergency, infecting more than 1 million Brazilians and many more throughout the Americas?
While health experts are unsure of the exact route Zika took, one hypothesis is that it arrived in Brazil during the 2014 World Cup.
The idea is that an infected traveler or athlete came to Brazil, along with thousands of others, for the World Cup in 2014. Then, presumably, a mosquito bit the traveler, contracted the virus, and went on to bite other humans, spreading the infection. Officials confirmed the first case in the country in May 2015. Since then, the virus — which is thought to cause birth defects — has infected 3 million to 4 million people throughout the Americas.