"Over the last 10 decades there have been about 30 newly emerging diseases that have the potential to be pandemics," says Dr. Larry Brilliant, an epidemiologist featured in CNN Films' "Unseen Enemy." More about 'Unseen Enemy' Go to CNN.com/unseenenemy for more stories and resources about epidemics, pandemics and the CNN Films documentary, "Unseen Enemy." "If we do nothing, it's not a matter of if there will be a global pandemic, it's just a matter of when -- and which virus, and how bad." In 2016, Zika was imported to the US by travelers who were infected while visiting areas where the virus was being transmitted. In July 2016 the first locally transmitted cases in the continental US were reported in Florida and in November 2016 local transmission was confirmed in Texas.

Source: CNN April 01, 2017 12:56 UTC