The virus has been spread throughout Latin and South America through mosquito bites. Now the CDC is examining 14 U.S. cases that may have involved sexual transmission. In three of those cases the infected were women whose only known risk factor was sexual contact with men who’d recently traveled to regions with active outbreaks. Several of the women were pregnant.
CNN's chief medical correspondent, Dr. Sanjay Gupta, answered questions about the virus last week via a Facebook chat.