Polio was eradicated in the U.S. decades ago. How has it returned? - Fortune

Most who contract the virus experience no symptoms, aiding its stealthy spread.

For many, polio conjures up black-and-white mental images of a bygone era and a pathogen relegated to the history bookslike former president U.S. President Franklin D. Roosevelt, who was largely conf… [+3174 chars]

full article...